Note: Descriptions are shown in the official language in which they were submitted.
WO 92~08687` ` PCl`/USS~1/06979
~ '
PROCESS FOR PREPARING N-ALKYL POLYHYDROXY AMINES IN AMINE
`~ AND AMINE/WATER SOLVENTS AND FATTY ACID AMIDES THEREFROM
2~3
-
FLELD OF-THE INyE-NTIoN
The present invention relates to a chemical process for
preparing N-alkyl polyhydroxy amines, especially N-methylgluc-
amine, as well as fatty acid derivatiYes thereof useful assurfactants.
.. .
BACKGROUND OF THE INVENTION
The manufacture of N-alkyl polyhydroxy amines, such as N~
methylglucamine, has been known for many years, and such materials
are available commercially. In the main, however, their use has
been somewhat limited and such materials have been relatively
expensive. Recently, there has been occasion to employ N-alkyl
polyhydroxy a~ines in reactions with fatty acid esters to prepare
fatty acid polyhydroxy amide detersive surfactants for use in
conven~ional home laundering products. As can be imagined, were
the cost of N-alkyl polyhydroxy amines to remain high, this
laundry detergent use of the fatty acid polyhydroxy amide surfact~
ants would be impossible. Accordingly, there is a continuing
search for quick, inexpensive means for preparing N-alkyl polyhy-
droxy amines on a commercial scale.
Moreover, it has been determined that care must be t~ken in
preparing~N-alkyl polyhydroxy amines in a form that is suitable
for subsequent reaction with ~atty acid methyl esters, since
contamination of the N-alkyl polyhydroxy amines with, for example,
hydrogenation catalysts such as Raney nickel, unreacted sugars~
water, N-methylglucosyl amine intermediates, and the like, can
seriously impact on the formation of the fatty acid polyhydroxy
amide formation. For example, browning reactions, with the
formation of undesirable color bodies, can occur, especially in
the presence of N-methylglucosyl amine. The formation of various
undesirable by-products such as cyclic materials and/or es$er-
amides can also occur. In a worst case scenario, by-product
WO 92/086B7 P~/US91/1)6979--.`
~9%~63 ` 2- ~
.
formation can be so high that the desired reaction of the N-alkyl
polyhydroxy amine with the fatty ac;d methyl ester is essentially
stopped in its entirety, with the formation of black, intractable
tarry products.
The present invention provides a simple means for preparing
N-alkyl polyhydroxy amines especially N-methyl glucamine, in high
yields, with low color formation, and in a form that is particu~
larly suited for subsequent reaction with fatty acid esters.
BACKGROUND ART
A number of years ago, processes were explored for making
textile assistants or detergents from fatty acids or their deriva-
tives in combination with N-alkylglucamines, the latter made by
reductive amination of glucose. Glucose reductive amination
processes are more fully disclosed in U.S. Patent 2,016,962, Flint
et al, issued October 8, 1935.
U.S. Patent 1,985,424, Piggott, issued December 25, 1934
discloses manufacturing "textile assistants" by reacting (a) the
product of heating-glucose and aqueous methylamine in presence of
hydrogen and a hydro~enating catalyst under pressure with (b) an
orga~ic carboxylic acid such as stearic acid or oleic acid. The
condensation product, prepared at about 160-C, is said to be
"predominantly, if not exclusively, an amide" and is assertedly
of the formula R-C0-NR~-CH2-~CHOH)~j-CH20H wherein R is an alkyl
radical containing at least 3 carbon atoms, while R1 is hydrogen
or an alkyl radical;
U.S. Patent 2,703,798, Schwartz, issued March 8, 1955 asserts
that compositions produced by reacting fatty acids or acid anhy-
; drides with N-alkylglucamines (presumably such as the process as
taught by Piggott) have poor color and poor detergency properties.
It is indeed chemically reasonable that more than one compound can
- be formed by the Piggott process. Piggott makes no attempt to
. quantitatively prove the structures of the compounds or mixtures
he prepared.
Schwartz ('798) goes on to report an improvement as a result r
o~ reacting fatty ester (as distinct from fatty acid or anhydride)
with N-alkylglucamines. Although this process may overcome one or
another deficiency of the art, such as of Piggott, it now tran- `
spires that the Schwartz process still has difficulties, in
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WO 92lO86~7 ` PCIIlJS91/û6979
0~25~3
particular, in that complex mixtures of compounds can be formed
even by the Schwartz process. The reaction may take several hours
and the process can fail to give high quality product. Neither
the process of Piggott not the process of Schwartz is known to
have ever borne fruit in commercial practice.
In more detail, Schwartz notes that only one of several
poss;ble chemical reactions takes place when N-monoalkylglucamines
are condensed with fatty esters or oils. The reaction is said to
give compounds formulated as amides, e.g.,
~ Rl
R2-C-N-CH2(CHOH)~-CH20H (I)
where R2 is fatty alkyl and Rl is a short-chain alkyl, typically
methyl. This structure is apparently the same as the structure
proposed by Piggott. Schwartz contrasts the single-product
outcome he believes he secures with compounds he asserts are
actually produced when acids are reacted with N-alkylglucamines,
namely mixtures of the amide (I) with one or more by-products, to
which he assigns esteramide and esteramine structures and which
assertedly include compounds which are ~in~rt and waxy, impairing
the surface activity of" the structure (I) amide.
According to Schwartz, approximately equimolar proportions of
N-monoalkylglucamines can be reacted with fatty alkyl esters by
heating at I40'C-230-C, preferably 160-C-180~C at normal, reduced
or superatmospheric pressures for a period "somewhat in excess of
one hour" during which time two initially immiscible phases merge
to ~orm a product said to be a useful detergent. .-~
Suitable N-monoalkylglucamines are illustrated by N-methyl-
gl~camine, N-ethylglucamine, N-isopropylglucamine and N-butylgluc-
amine. Suitable fatty alkyl esters are illustrated by the product
of reacting a C6-C3~ fatty acid with an aliphatic alcohol e.g.,
methyl ester of lauric acid. Mixed glycerides of Manila oil or
mixed glycerides of cochin coconut oil can apparently also be used
as the fatty ester. When the glucamine is N-methylglucamine, the
corresponding products with these fatty esters are characterized
as the "fatty acid amides of N-methylglucamine", which are useful
detergent surfactants. Another specific composition reported is
assertedly "N-isopropylglucamine coconut fatty acid amide".
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9 2 5 6 3 4 PCT/US91/06979
U.S. Patent 2,993,887, ~ech, issued July 25, 1961 reveals
there is even more complexity to the reactions of fatty substances
with N-methylglucamine. In particular, Zech asserts that the
products of high-temperature reaction (180~C-200 C) within the
range disclosed by Schwartz have cyclic structures. No fewer than
four possible structures are given. See '887 at column 1, line 63
- column 2, line 31.
What is now believed actually to be provided by the fatty
ester- N-alkylglucamine process of Schwartz are compositions
comprising mixtures of formula (I) compounds together with
appreciable proportions (e.g., about ?5%, often much more) of
several other components, especially cyclic glucamide by-products
(including but not limited to the structures proposed by Zech) or
related derivatives such as esteramides wherein as compared with
formula (I) at least one -OH moiety is esterified.
~oreover, a reinvestigation of Schwartz suggests that there
are other significant unsolved problems in the process, including
a tendency to form trace materials imparting very unsatisfactory
color and/or odor to the product.
More recently, the work of Schwartz notwithstanding, Hildreth
has asserted that compounds of formula ~I) are new. See Biochem.
J., 1982, Yol. 207, pages 363-366. In any event, these composi-
tions are given a new name: "N-D-gluco-N-methylalkanamide deter-
gentsn, and the acronym "MEGAn. Hildreth provides a solvent~
assisted process for making the compounds differing seminally from
Schwartz in that it returns to the use of a fatty acid reactant,
instead of fatty ester. Moreover, Hildreth relies on pyrid-
ine/ethyl chloroformate as the solventtactivator. This process is
specifically illustrated ~or octanoyl-N-methylglucamide ("OMEGA"),
nonanoyl-N-methylglucamide ("MEGA-9") and decanoyl-N-methylgluc-
a~ide ("MEGA-10"). The process is said to be cheap and high-
yield. One must of course assume that "cheap" is relative and is
meant in the sense of specialized biochemical applications of
interest to the author: in terms of large-scale detergent manufac-
ture~ the use of pyridine and ethyl chloroformate would hardly be
viewed as consistent with an economic or environmentally attrac-
tive process. Therefore, the Hildreth process is not ~urther
considered herein.
.... . . ..
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w 0 92/0~687 , PCI/Us9l/06n9 ¦~
~ - 5 - 2~92~3 ~
Hildreth and other workers have purified certain formula (I)
compounds, e.g., by recrystalli2ation, and have described the
properties of some of the structure ~I) compounds. Recrystal-
lization is, of course, a costly and potentially hazardous
(flammable solvents) step in itself, and large-scale detergent
manufacture would be more economical and safer without it.
According to Schwartz suprd, the products of the Schwart7
process can be used for cleaning hard surfaces. According ~o
Thomas Hedley & Co. Ltd. (now Procter & Gamble), British Patenk
809,060 published February 18, 1959, formula (I) compounds are
useful as a surfactant for laundry detergents such as those having
granular fsrm. Hildreth (supra) mentions use of compounds of
formula (I) in the biochemistry field as a detergent agent for
solubilizing plasma membranes and EP-A 285,768, published ~ecember
10, 1988 describes application of formula (I) compounds as a
thickener. Thus, these compounds, or compositions containing
themS can be highly desirable surfactants.
Yet another process for making compositions comprising
formula ~I~ compounds is included in the above-identified
disclosure of improved thickeners. See EP-A 285,768. See also Ho
Kelkenberg, Tenside Surfactants Detergents 25 (1988) 8-13, inter
a77a for additional disclosures of processes for making
N-alkylglucamines which, along with the above-identified art~
disclosed N-alkylglucamine processes can be combined with the
instant process for an overall conversion of gluccse and fatty
materials to useful surfactant compositions.
The relevant disclosures of EP-A 285,768 include a brief
statement to the effect that "it is known that the preparation of
chemical compounds of formula (I) is done by reacting fatty acids
or fatty acid esters in a melt with polyhydroxy alkylamines which
can be N-substituted, optionally in the presence of alkaline
catalysts". The above-referenced art strongly suggests that this
; statement is a gross simplification or is inaccurate. EP-A
285,768 does not cite any references in support of the quoted
statement, nor has any reference other than EP-A 285,768 been
found which actually does disclose any catalytic condensation of
N-alkylglucamines with fatty esters or fatty triglycerides.
`
WO 92/08687 2 ~ ~ 2 ~ 6 3 ` PCI /US91/0697~ I
The European Patent Application contains the following
Example entitled "Preparation of N-methy1-coconut fatty acid
glucamide" in which "Na methylate" is understood to be synonymous
with "sodium methoxide" and which has been translated from the
German: r
In a stirred flask 669 g (3.0 mol) of coconut fatty
acid methyl ester and 585 9 (3.0 mol) of N-methyl '
glucamine with the addition of 3.3 9 Na methylate were
gradually heated to 135C. The methanol formed during
` the reaction was condensed under increasing vacuum a~. ¦
IOO to 15 mbar in a cooled collector. After the meth~
anol evolution ended the reaction mixture was dissolved
in 1.5 l of warm ;sopropanol, f;ltered and crystallizedO
After filtration and drying 882 9 (576% of theoretical)
of waxy N-methyl coconut fatty acid glucamide was
obtained. Softening point ~ 80 to 84'C; Base number: 4
mg. KOH ~9.
EP-A 285,768 continues with the following:
"In a similar manner the ~ollowing fatty acid glucamides were
~0 prepared:
Yield Softening Point Base NoO
% (~C) (mg. KOH/g~ i
N-methyl lauric acid glucamide 76 94-96 6
~ N-methyl myristic acid glucamide~ .75;~! 98-100 3
N-methyl palmitic acid glucamide 75 103-lOS 5
N-methyl stearic acid glucamide 84 96-98 ~"
To summarize some important points of what can be gleaned
from the art, the aforementioned Schwartz patent teaches that the
problem of making formula (I) compounds from ~atty esters or
triylycerides and an N-alkylglucamine is solved by selecting ~atty
ester (instead of fatty acid) as the ~atty reactant, and by doing
simple uncatalyzed condensations. Later literature, such as
Hildreth, changes direction back to a fatty acid-type synthesis9
but does not document either that the teaching of the Schwartz
patent is in error or how, short of making highly pure formula (~i~
compounds, to make such surfactants to detergent formulator's
specifications. On the other hand, there has been one disclosure,
W o 92/08687 ~. PCT/US9~t~7~ -
- 7 ~
in a totally different technical field, of sodium methoxide-
catalyzed formula (I) compound synthesis. As noted, the procedure
involves gradual temperature staging up to 135'C and
recrystallizing the product.
SUMMARY OF THE INVENTION
The present invention encompasses a process (carried out
under non-oxidizing conditions) for preparing N-alkyl polyhydroxy
amines, comprising the steps of: `
; a) reacting a reducing sugar or reducing sugar derivative
with a primary amine reactant in an` amine solvent at
mole ratios of amine:sugar not greater than about 30~1
to provide an adduct;
b) reacting said adduct from step (a) dissolved in said
solvent with hydrogen under mild conditions in the
presence of a metal catalyst; and
c) removing said catalyst and substantially removing the
water and unreacted amines from the reaction mixture to
secure the N-alkyl polyhydroxy amine.
A preferred process herein is wherein the sugar material is a
reducing sugar, especially glucose, and the amine compound is a
member selected from the group consisting of Cl-C~ alkyl or
hydroxyalkyl amines. When the amine (both reactant and solvent~
is monomethyl amine thereinafter, simply "methyl amine") and the
sugàr is glucose, the preferred ~reaction product N-methylgluca~ne
is secured. A particular advantage of the present process is that
it can be carried out in the presence of water in step (a~.
Accordingly, raw materials such as corn syrup, hydrated glucose,
and the like, can be used as the sugar source.
The catalyst used in step (b) is preferably a nickel
catalyst, especially nickel on a substrate such as silica or
silica/alumina. Raney nickel can also be used, but is less
preferred.
Step (a) of the process is preferably carried out at a
temperature of from about O-C to about 80~C, preferably from about
30C to about 60-C. Step tb) of the process is preferably carried
out at a temperature of from about 40~C to about 120-C, preferably
from about 50C to about 90'C. Steps (a) and (b) of the R-1
process are preferably conducted under non-oxidizing conditions
WO 92/08687 '` ' ` PCI /US91/06979 ~ .
;~g~5~ -8- ~ . ~
- (e.g., inert gas) to provide good color. Catalyst removal is, of
course, done under inert conditions due to fire hazard.
The invention herein also encompasses an overall process for
preparing polyhydroxy fatty acid amide surfactants which includes
an amide-forming reaction comprising reacting the N-alkyl polyhy
droxy amine materials prepared in the foregoing manner with fatty
acid esters in an organic hydroxy solvent in the presence of a
? base catalyst. The formation of such surfactants with high
conversionsS high purity and low color is an especially beneficii~
result of the present process, since it allows the detergent
formulator to pump or otherwise incorporate the polyhydroxy fatty
acid amide reaction product plus the reaction solvent such as
1,2-propylene glycol, glycerol, or alcohol (e.g., in liquid
detergents) directly into the final detergent formulation. This
offers economic advantages in that a final solvent removal step is
rendered unnecessary, particularly where glycols or ethanol is
used.
Moreover, the process herein allows the formulator to prepare
high quality polyhydroxy fatty acid amide surfactants without
~o purification of the N-alkylglucamine.
All percentages, ratios and proportions herein are by ~eight7
unless otherwise specified.
DETAILED DESCRIPTION OF THE-IN~ENTIQN
- The reaction for the preparation of the polyhydroxyamines
herein can be termed the ~R-1" reaction, and is illustrated by the
formation of N-methylglucamine, wherein R1 is methyl.
CH3NH2(xs)
R1NH2 + glucose , Adduct ~ H20
- catalyst
Adduct + H2 ~ R~N(H)CH2(CHOH)4CH20H
The reactants, solvents and catalysts used in the R-1
reaction are all well-known ~aterials which are routinely avail
able from a variety of commercial sources. The following are
nonlimiting examples of materials which can be used herein.
Amine_Material - The amines useful in the R-1 reaction herein
are primary amines of the formula RlNHz, wherein R~ is, for
example, alkyl, especially C1-C4 alkyl, or Cl-C4 hydroxyalkyl.
Examples include methyl, ethyl, propyl, hydroxyethyl, and the
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W092/08687` :~ PCI'/US91/06979-~-
- 9 - ; ~2b92563
like. Nonlimiting examples of amines useful herein include methyl
amine, ethyl amine, propyl amine, butyl amine, 2-hydroxypropyl
amine, 2-hydroxyethyl amine; methyl amine is preferred. All such
amines are sometimes jointly referred to as "N-alkyl amines".
Polvhvdroxv Material - A preferred source of polyhydroxy
materials useful in the R-l reaction comprises reducing sugars or
reducing su~ar derivatives. More specifically, reduc;ng sugars
useful herein include glucose (preferred), maltose, fructose~
maltotriose, xylose, ~alactose, lactose, and mixtures thereof.
-Catalvst - A variety of hydrogenation catalysts can be used
in the R-1 reaction. Included among such catalysts are nickel
~preferred), platinum, palladium, iron, cobalt, tungsten, various
hydrogenation alloys, and the like. A highly preferred catalyst
herein comprises "United Catalyst G49B" a particulate Ni catalyst
supported on silica, available from United Catalysts, Inc.9
Louisville, Kentucky.
Solvent - Formation of the adduct in the R-l process is
carried out using an excess of the amine as the solvent. The
excess amine also is used in the subsequent reaction with
hydrogen. Optionally, the amine can be replaced with an alcohol 7
such as methanol, for the hydrogen reaction. Typical examples of
solvents useful herein in the formation of the amine-sugar adduct
include methyl amine, ethyl amine, and hydroxyethyl amine; methyl
amine is preferred; methyl amine/water solvent can also be usedO
~eneral R-1_Reaction Conditions - Reaction conditions for the
R-1 reaction are as follows.
(a) Adduct formation - The reaction time used for adduct
formation will typically be on the order of 0.5-20
hours, depending somewhat on the reaction temperature
chosen. In general, lower reaction temperatures in the
range of O-C-80-C require longer reac~ion times~ and
vice-versa. In general, over the preferred 30-C 60-0
reaction temperature range, good adduct yields are
achieved in 1-10 hours. Generally good adduct formation
is achieved at about a 4:1 to 30:1 mole ratio of
amine:sugar. Typical sugar reactant concentrations in
the amine solvent are in the 10%-60% (wt.) range.
- . . . .
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WO g2/08687 ` - - P~/US91/069759 .
~o~`~S63 10- ~ ,
Adduct formation can be carried out at atmospheric or
superatmospheric (preferred) pressures.
(b) Reaction with Hydroqen - The reaction with hydrogen can
' ' typically be run, for example, at temperatures of
40-C-120'C at 50-1,000 psi or,'for example, at 50'C-90~C
at 100-500 psi for periods of 0.1-35 hours, generally
0.5-8 hours, typically 1-3 hours. The adduct/solvent
' ' solution used in the hydrogen reaction is typically at a
; 10%~60% twt.) solute level'.' tIt will be' appreciated
10 ' i that the selection of hydrogen reaction conditions wi'll
depend somewhat on the type of pressure equipment
available to the formulator, so the above-noted reaction
conditions can be varied without departing from this
invention.) Hydrogen reaction catalyst levels are
typically 1% to 40%, preferably about 2% 'to about 30%
solids weight, calculated based on wt. catalyst:wtO
reducing sugar substituent for batch processes. Of
course, continuous processes could be run at much higher
catalyst levels. The produet of step (b~ can be dried
by solvent/water stripping, or by crystallization.9
trituration, or by means of effective drying ayPnts.
' EXAMPLE I
- ' Anhydrous glucose (36.00 9; Aldrich Chemical `Company) is.
" wëighed'into a giàss~liner. The glass liner is plàced into a
dry-ice bath and methyl amine gas (68.00 9; Matheson) is condensed
~! into the glass liner. The liner is then loaded into a rocking
', ' autoclave (500 ml capacity). The'autoclave is heated to 50~C and
rocked for 5 hours at 50'C under 600 psig nitrogen to form the
adduct (N-methylglucosylamine). The reaction is then cooled in a
dry-ice bath. The autoclave is then vented cold. Raney nickel
~ ' ~7.Z g of a 50% suspens;on in water, W/2 type, Aldrich Chemical
;~ ` Company) is added. The reaction is heated to 50-C under 500-600
' ~ psig hydrogen and is rocked for 16 hours. The reaction is cooled
in dry-ice bath and vented and purged with nitrogen. The reaction
solution is pressure filtered through a Zeofluor filter (PTFE, 47
mm, 0.5 micron filter) with a 4 inch bed cf Celite 545 (Fisher
Scientific Company). The ~iltrate is concentrated under a stream
of nitrogen to give 8.9 9 of white solid. The Celite plug is
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WO 92/08687 PsCr/US91/~7~
~ 11 ~'9'~
washed with about 300 mls of water and the water is stripped on a
rotary evaporator to give 18.77 9 of ~hite solid. The two solids
are combined as they are analyzed to be of similar compasition
(90+ purity by GC analysis). The product is N-methyl glucamineO
EXAMPLE II
The process of Example I is repeated in a stirred autoclave
fitted with a fritted exit filter, a triple impeller stirrer~
outlet and inlet tubes and a baffle. Reagents and reaction
conditions for the preparation of N-methyl glucamine are as
follows: 15 9 of 20% G49B catalyst (Ni/silioa; United Catalyst~
and 75 g glucose powder (Aldrich, Lot 07605LW) are slurried in 160
mls methanol and pretreated with H2 ~or one hour (50'C). The
mixture is then-cooled and the methanol is removed by pressure.
The reactor is cooled to less than 5C and charged with 76
mls of liqui~ methyl amine.
The reaction mixture is slowly heated to 60-C over 46 minutes
at 250 psi hydrogen and sampled. Heating is continued at 60-C for
20 minutes and sample 2 is taken. Heating is continued at 60-C
for 46 m;nutes ~sample 3) and then at 60-C for 17 minutes (sample
4). The reaction mix is heated to 70-C for an additional 33
minutes (sample 5). Total reaction time is 2.7 hours. The dried
product is 93.2~ N-methyl glucamine ~GC analysis).
. The polyhydroxyamine products of the aforesaid R-I reaction9
preferably with water substantially removed, are desirable and can
be further employed in an amide-forming reaction which is desig
nated herein as the nR-21~ reaction. A typical R-2 amide-forming
rèaction herein can be illustrated by the formation of lauroyl
N-methyl glucamide, as follows.
methanol
R2COOMe + MeN(H)CH2(CH~H)~CH20H
methoxide
R2C(Q)N(Me)CH2(CHOH)4CH20H + MeOH
wherein R2 is CllH23 alkyl.
Thus, the i m ention herein encompasses an overall process for
preparing polyhydroxy fatty acid amide surfactants, all as noted
above for the R-1 process, comprising:
(a) reacting a reducing sugar (preferably glucose) or
reducing sugar derivative with an amine reactant
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WO 92/ûR687 ' ` PCI /US91/0697~
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'~ ~ 9 ~ S ~ ~eferably methyl amlne) in an. amine solvent
~preferably, methyl aminej to provide an adduct;
(b) react;ng sa;d adduct from step (a) dissolYed in said
amine solvent with hydrogen in the presence of a metal
catalyst; ` ~ j
(c) removing said catalyst and substantially removing water
and excess amine solvent from the reaction mixture to
provide the polyhydroxyamine reaction producti and9
~ thereafter, per the R-2 process,
10 (d) reacting said substantially anhydrous polyhydroxyamine
product from step (c) with a fatty acid ester in an
organic hydroxy solvent (preferably, methanol or ::
propylene glycol) in the presence of a base catalyst to ~ :
form the polyhydroxy fatty acid amide surfactant
~preferably, at a temperature below about lOO-C); and
(e) optionally, when the reaction step (d) is essentially
complete, removing said solvent used in step td).
More specifically, the combination of R-l and R-2 reactions
herein provides an overall process (R-l plus R-2) which can be
used to prepare polyhydroxy fatty acid amide surfactants of the
formula: .
0 R
(I) R2 - C - N - Z
wherein R1 is H, Cl-C~ hydrocarbyl, 2-hydroxyethyl, 2-hydroxy
propylt or a mixture $hereof, preferably C~-CI alkyl, ~ore
preferably C~ or C2 alkyl, most preferably Cl alkyl (iOeO 9
methyl); and R2 is a Cs-C3, hydrocarbyl moiety, preferably
straight chain C~-Clg alkyl or alkenylg ~ore preferably straight
chain C9-C1~ alkyl or alkenyl, most preferably straight chain
Cl~-C~7 alkyl or alkenyl, or mixture thereof; and Z is a
polyhydroxyhydrocarbyl moiety having a linear hydrocarbyl chain
with at least 3 hydroxyls directly connected to the chain, or an
alkoxylated derivative (preferably ethcxylated or propoxylated)
thereof. Z preferably will be derived from a reducing sugar in a
reductive amination reaction; more preferably Z is a glycityl
moiety. Suitable reducing suyars include glucose, fructose,
maltose, lactose, galactose, mannose, and xylose. As raw
materials, high dextrose corn syrup, high fructose corn syrup, and
.
.
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W O 92/08687 ' PCT/US91/06g7~
- 13 - `
high maltose corn syrup can be ut;lized as well as the ind;vidual
sugars listed above. These corn syrups may yield a mix of sugar
components for Z. It should be understood that it is by no means
intended to exclude other suitable raw materials. Z preferably
will be selected from the group consisting of -CH2-~CHOH)n-CH20H~
-CH(CH20H)-~CHOH)n 1-CH20H, -CH2-(CHOH)2(CHOR')(CH~H)-CH20H, where
n is an integer from 3 to 5, inclusiYe, and R' is ~ or a cycl jG
mono- or poly- saccharide, and alkoxylatecl derivatives thereofY
Most preferred are glycityls wherein n is 4, particularly
-CH2-(CHOH)~-CH20H.
In Formula (I), R1 can be, for examp'le~ N-methyl, N~ethyl9
N-propyl, N-i'sopropyl, N-butyl, N-isobutyl, N-2-hydroxy ethyl, or
N-2-hydroxy propyl.
R2-C0-N< can be, for example, cocamide, stearamide, oleamide~
lauramide, myristamide, capricamide, palmitamide, tallowamide,
etc.
Z can be ~-deoxyglucityl, 2-deoxyfructityl, 1-deoxymaltityl 9
1-deoxylactityl, 1-deoxygalact~tyl, 1-deoxymannityl, 1-deoxymalto-
triotityl, etc.
The following reactants, catalysts and solvents can con~en~
iently be used in the R-2 reaction herein, and are listed only by
way of exemplification and not by way of limitation. Sueh
'' materials are all well-known and are routinely avail~ble from a
'9 ~ariety of commercial sources. ''
~553n~ - Various fatty esters can be used in the R~2
reaction, including mono , di- and tri-esters (i.e., triglycer
ides). Methyl esters, ethyl esters, and the like are all quite
'suitable. The polyhydroxyamine reactants include reactants
available from the above-described R-1 reaction, such as N-alkyl
and N-hydroxyalkyl polyhydroxyamines with the N-substituent group
such as CH3-, C2H5-, C3H7-9 HOCH2CH2-, and the like. (Polyhy-
droxyamines available from the R-1 reaction are preferably not
contaminated by the presence of residual amounts of metallo
hydrogenation catalysts, although a few parts per million ~eOg.,
1-20 ppm~ can be present.) Mixtures of the ester and mixtures of
the polyhydroxya~ine reactants can also be ussd.
Catalvsts - The catalysts used in the R-2 reaction are basic
materials such as the alkoxides (preferred)9 hydroxides (less
... . . . ... . . . . . . .
., . . .. . .. . . ~ . : : : . . : ,
w O 9l/08687 PCT~U5~1/0697~ ¦
~ a g ~ }4 -
preferred due to possible hydrolysis reactions), carbonates, and
the like. Preferred alkoxide catalysts include the alkali metal
~1-C~ alkoxides such as sodium methoxide, potassium ethoxide, and
the like. The catalysts can be prepared separately from the
reaction mixture, or can be generated in sitv using an alkali
metal such as sodium. For in situ generation, e.g., sodium metal
in the methanol solvent, it is preferred that the other reactants
not be present until catalyst generation is complete. The
catalyst typically is used at a level of about 5 mole X of the
ester reactant. Mixtures of catalysts can also be used.
So1vents -The organic hydroxy solvents used in the R-~
reaction include, for example, methanol, ethanol, propanol,
iso-propanol, the butanols, glycerol, 1,2-propylene glycol~
1,3-propylene glycol, and the like. Methanol is a preferred
alcohol solvent and 1,2-propylene glycol is a preferred diol
solvent. Mixtures of solvents can also be used.
General R-2 Reaction ~onditions - It is an objective herein
to prepare the desired products while minimizing the formation of
cyclized by-products, ester amides and color bodies.. Reaction
temperatures below about 135-C, typically in the range of from
about 40-C to about 100-C, preferably 50'C to 80-C, are used to
achieve this objective, especially in batch processes where
reaction times are typically on the order of about 0.5-2 hours, or
even up to 6 hours. Somewhat higher temperatures can be tolerated
in continuous processes, where residence times can be shorter.
The following examples are intended to illustrate the
practice of the R-2 reaction using the N-palyhydroxyamines
prepared by the above-disclosed R-1 reaction (w;th H20 having been
substantially removed), but are not intended to be limitins
thereof. It is pointed out that the concentration ranges of the
reactants and solvent in Example III provide what can be termed a
"70% ~oncentrated" (with respect to reactants) reaction mixture.
This 70% concentrated m;xture provides good results, in that high
yields of the desired polyhydr~xy fatty acid amide product are
3~ secured rapidly. Indeed, indications are that the reaction is
substantially complete within one hour, or less. The consistency
of the reaction mixture at the 70% concentration level provides
ease of handling. However, even better results are secured at the
WO 92/08687 , . . PCr/US91/06979 ...
- 15 . ~92563
80% and 90% concentration levels, in that chromotography data
indicate that even less of the undesired by-products are formed at
these higher concentrations. At the higher concentrations the
reaction systems are somewhat more difficult to work with, and
require more efficient stirring (due to their initial thickness3
and the like, at least in the early stages of the reaction. Once
the reaction proceeds to any appreciable extent, the viscosity of
the reaction system decreases and ease of mixing increases.
EXAMPLE III
The product o~ Example I (9.00 9, 0.0461 moles, N-methyl~
glucamine) is combined with 8.22 g methanol anhydrous in a round
bottom flask fitted with condenser, drying tube and argon blanketO
The reaction methanol and N-methylglucamine are heated to reflux
for 15 minutes. Sodium me~hoxide (0.1245 9, Q.0023 moles, Aldrich
1~ Chemical Company) and methyl ester (10.18 9, 0.0461 moles, Procter
& Gamble CE1270, includes C12-C1B fatty acid esters) are added and
reaction continued at reflux for 3 hours. Methanol is then
removed under reduced pressure to give essentially colorless white
product. Yields are not reported since samples were taken during
2~ reaction at 30 minutes, 1 hour, 2 hours and 3 hours before dryingO
The dried sample is washed with cold methanol and filtered and
final drying is done under vacuum to give 10.99 g of the poly-
hydroxy fatty acid amide detergent.
EXAMPLE IV
An uverall process at the 80% reactant concentration level
for the amide synthesis is as follows.
A reaction mixture consisting of 84.87 9. fatty acid methyl
ester (source: Procter & Gamble methyl ester CEl270)1 75 gO
N-methylglucamine per Example I, above, 1.04 9. sodium methoxide
and a total of 39.96 9. methyl alcohol (ca. 20% by wt. of reaction
- mixture) is used. The reaction vessel comprises a standard refluxset-up fitted with a drying tube, condenser and mechanical
stirring blade. The N-methyl glucamine/methanol is heated with
stirring under argon (reflux). After the solution has reached the
desired temperature, the ester and sodium methoxide catalyst are
added. The reaction mixture is maintained at reflux for 6 hours.
The reaction is essentially complete in 1.5 hours. After removal
of the methanol, the recovered product weighs 105.57 grams.
wo g2/08687 2 o 9 '~ ~ 6 3 PCT/US91t~7~
~ 16 -
Chromatography indicates the presence of only traces of undesired
ester-amide by-products, and no detectable cyclized by-product.
EXAMpLE V
The process of Example IV is repeated at the 90% reactant
level for the polyhydroxy fatty acid amide synthesis step. Levels
of undesirable by-products are extremely low, and reaction is
essentially complete at 30 minutes. In an alternate mode9 khe
reaction can be initiated at a 70% reactant concentration~ ~or
example, ~nd methanol can be stripped during the course aF khe
reaction and the reaction taken to completion.
EXAMPLE VI
The process of Example III is repeated in ethanol (99%) and
1,2-propylene glycol (essentially dry), respectively, with good
product formation. In an alternate mode, a solvent such as
1,2-propylene glycol is used in the R^2 step, with meth~nol
stripping throughout the process. The resulting surfactant/glycol
mix can be used directly in a detergent composition.
Having thus disclosed reaction conditions involving amine
solvents in the R-1 step of- the instant process, it has now
further been determined that mixtures of amine/water solvents for
use in R-l affords still additional advantages in the R-1
reaction. ~n particular, the use of an amine/water solventO
yields substantially no color formation in the reaction product9
gives high product -yields relatively quickly; and leaves
essentially no reducing sugars in the reaction product, which ean
contribute to color formation in the subsequent R-2 reaction. The
R-1 reaction in a mixed amine/wate~ solvent is as follows.
EXAMP E VII
Using a stirred autoclave and procedure per Example II, 15 9
of the 649B catalyst, glucose powder (75 9; Aldrich) and 160 mls
methanol are slurried and treated with H2 to remove oxide ~rom the
catalyst surface. Methanol is removed. 80 mls (52.8 9) of methyl
amine are added to the glucose/catalyst mixture at below 5-C9 and
22 mls water are added at room temperature.
The reaction mixture is heated to 70-C in 34 minutes and held
at 70-C for 40 minutes, during the hydrogenation. The H20/methyl
amine solution of the reaction product is blown out of the reactor
WO 92/08687 PC1 /US91;06~79
~$ - 17 - ~;~092~63
through the frit tremoves catalyst) and dried to yield the
N-methylglucamine product.
When using the mixed amine/water solvent, weight ratios of
amine (especially, methyl amine) and water in a range of from
about 10:1 to about 1:1 are typically employed. The R-1 reaction
product, substantially free from water (preferably, less ~han
about 1%, more preferably, less than about 0.3% by weight of
water) can then be used in the R-2 reaction 1;o prepare polyhydroxy
fatty acid amides, as described above.
While the foregoing disclosure generally relates to
solvent-assisted method fnr preparing N-methyl polyhydroxy amines~
such as N-methyl glucamine, as well as their fatty acid amide
derivatives using fatty methyl esters, it is to be understood that
variations are available which do not depart from the spirit and
scope of this inYention. Thus, reducing sugars such as fructose~
galactose, mannose, maltose and lactose, as well as sugar sources
such as high dextrose corn syrup, high fructose corn syrup and
high maltose corn syrup, and the like, can be used. to prepare the
polyhydroxyamine material (i.e., to replace glucamine) of the
reaction. Likewise, a wide variety of ~ats and oils (triglycer~
ides) can be used herein in place of the fatty esters exemplif;ed
above. For example9 fats and oils such as soybean oil, cottonseed
oil, sunflower oil, tallow, lard, safflower oil, corn oil, canola
`oii; peanut ôil, fish oil, rapeseed o;l, and the like, or hardened
(hydrogenated) forms thereof, can be used as the source of tri-
glyceride esters for use in the present process. It will be
appreciated that the manufacture of detersive surfactants from
such renewable resources is an important advantage of the present
process. The present process is particularly useful when prepar-
ing the longer-chain (e.g., C1R) and unsaturated fatty acid
polyhydroxy amides, since the relatively mild reaction
temperatures and conditions herein afford the desired products
with minimal by-product formation. A pre-formed portion of the
polyhydroxy fatty acid amide surfactant can be used to assist
initiation of the R-2 amide-forming reaction when triglycerides or
the longer-chain methyl esters are used as reactants.
Furthermore, use of propylene glycol, or glyoerine, or preformed
mono esters thereof, can assist in initiation of the R-2 reaction,
W O 92/0$687 ` ` PCT/US91/06979
~ o 9 2 ~ ~ 3 - 18 - `
as wel . It has further been determined that surfactant yields in
the R-2 process can be increased by simply storing the solidified
product (which contains some minor amount of entrained solvent and
reactants) e.g., at 50-C, for a few hours after removal from the
reaction vessel. Storage in this manner apparently allows the
last fraction of unreacted starting materials to continue to form
the desired polyhydroxy fatty acid amide surfactant. ~hus, y;e1ds
can be increased appreciably, i.e., to a high degree ~ of
completion, which is an important consideration in large-scale
industrial processes.
The invention encompasses the use of the above-described
surfactant products of the overall R-1 plus R-2 process to prepare
fully-formulated detergent compositions using a wide variety of
surfactants, builders and optional detersive adjuncts and other
ingredients well-known to detergent formulators can be used in
such compositions, all at conventional usage levels. Accordingly7
the present invention also encompasses a process for preparing a
fully-formulated laundry detergent composition, or the like9
comprising admixing the solvent-containing reaction produet of the
polyhydroxy fatty acid amide-forming R-2 reaction with otherwise
conventional detersive surfactants and detersive adjuncts.
The following is not intended to limit the invention herein9
but is simply to further illustrate additional aspects of th@
tefhnology which may be considered by the formulator in th@
manufacture of a wide variety of detergent compositions using the
polyhydroxy fatty acid amides.
It will be readily appreciated that the polyhydroxy fatty
acid amides are, by virtue of their amide bond, subject to some
instability under highly basic or highly acidic conditions. While
some decomposition can be tolerated, it is preferred that these
materials not be subjected to pH's above about 11, preferably 10,
nor below about 3 for unduly extended periods. Final product pH
(l~quids) is typically 7.0~9.0 and up to about 10.5 or 11 for
solids.
During the manufacture of the polyhydroxy fatty acid amides
it will typically be necessary to at least partially neutrali~e
the base catalyst used to form the amide bond. While any acid can
be used for this purpose, the detergent formulator will recogni~e
,., ..,, ...~
; : :
WO 92/08687 ` PCl`/US91/06975D
(~ - lg ` ~25~3
that it is a simple and convenient matter to use an acid which
provides an anion that is otherwlse useful and desirable in the
finished detergent composition. For example, citric acid can be
used for purposes of neutralization and the resulting citrate ion
(ca. 1%) be allowed to remain with a ca. 40% polyhydroxy fatty
acid amide slurry and be pumped into the later manufacturing
stages of the overall detergent-manufacturing process. The acid
forms of materials such as oxydisuccinate, nitrilotriacetate~
ethylenediaminetetraacetate, tartrate/succinate, and the like, can
be used similarly.
The polyhydroxy fatty acid amides derived from coconut alkyl
fatty acids ~predominantly C,2-C1~) are more soluble than their
tallow alkyl (predominantly C16-C~8) counterparts. Accordingl~y~
the C12-C1~ materials are somewhat easier to formulate in liquid
compositions, and are more soluble in cool-water laundering baths
However, the C~5-C~8 materials are also quite useful, especially
under circumstances where warm-to-hot wash water is used. Indeed9
the C,6-C10 materials may be better detersive surfactants than
their C12-C14 counterparts. Accordingly, the formulator may wish
to balance ease-of-manufacture vs. performance when selecting a
particular polyhydroxy fatty acid amide for use in a gi~en
formulation.
It will also be appreciated that the solubility of the
polyhydroxy fatty acid amides can be increased by having points of
unsaturation and/or chain branching in the fatty acid mo;etyO
Thus, materials such as the polyhydroxy fatty acid amides deri~ed
from oleic acid and iso-stearic acid are more soluble than their
n-alkyl counterparts.
Likewise, the solubility of polyhydroxy fatty acid amides
prepared fro~ disaccharides, trisaccharides, etc., will ordinarily
be greater than the solubility of their monosaccharide-derived
counterpart materials. This higher solubility can be of
particular assistance when formulating liquid compositionsO
Moreover, the polyhydroxy fatty aeid am;des wherein the
polyhydroxy group is derived from maltose appear to function
especially well as detergents when used in combination with
conventional alkylbenzene sulfonate (nLAS") surfactants. While
not intending to be limited by theory, it appears that the
:
W o 92/08~87 -` PCT/US91/06979 '~t
` 2 0 9 2 ~ ~ 3 - 20 - ~
combination of LAS with the polyhydroxy fatty acid amides derived
from the higher saccharides such as maltose causes a substantial
and unexpected lowering of interfacial tension in aqueous media,
thereby enhancing net detergency performance. (The manufacture of
5a polyhydroxy fatty acid amide derived from maltose is described
hereinafter.)
The polyhydroxy fatty acid amides can be manufactured not
only from the purified sugars, but also from hydrolyz~d starches9
e.g., corn starch, potato starch, or any other convenient plant- i
10derived starch which contains the mono-, di-, etc. saccharide
desired by the formulator. This is of particular importance from
the economio standpoint. Thus, "high glucose" corn syrup, "high
maltosel' corn syrup, etc. can conveniently and economically be
used. De-lignified, hydrolyzed cellulose pulp can also provide a
15raw material source for the polyhydroxy fatty acid amides.
As noted above, polyhydroxy fatty acid amides derived from
the higher saccharides, such as maltose, lactose, etc., are more
soluble than their glucose counterparts. Moreover, it appears
that the more soluble polyhydroxy fatty acid amides can help
20solubilize their less solubl2 counterparts, to varying degrees~
Accordingly, the formulator may elect to use a raw material
comprising a high glucose corn syrup, for example, but to select a
syrup which contains a modicum of maltos2 (e.g., 1% or more). The
resulting mixture of polyhydroxy fatty acids will, in generalD
25exhibit more preferred solubility properties over a broader range
of temperatures and concentrations than would a "pure" glucose-
derived polyhydroxy fatty acid amide. Thus, ;n addition to any
economic advantages for using sugar mixtures rather than pure
sugar reactants, the polyhydroxy fatty acid amides prepared from
30mixed sugars can offer very substantial advantages ~ith respect to
performance and/or ease-of-formulation. In some instances9
however, some loss of grease removal per~ormance (dishwashing) may
be noted at fatty acid maltamide leYels above about 25% and some
loss in sudsiny above about 33% (said percentages being the
35percentage of maltamide-derived pslyhydroxy fatty acid amide vsO
glucose-derived polyhydroxy fatty acid amide in the m;xture).
This can vary somewhat, depending on the chain length of the fatty
acid moiety. ~ypically, then, the formulator electing to use such
w 0 s2io~6s7~ i PCTIU~91/~97
. .. 21 i2 ~ 9 2 ~'~ 3
mixtures may find it advantageous to select polyhydroxy fatty acid
amide mixtures which conta;n ratios of monosaccharides (e.g~9
glucose) to d;- and higher saccharides (e.g., maltose) from about
: 4:1 to about 99:1. .
It has now been determined that it may be convenient for the
formulator of., for example, liquid detergents to conduct such
processes in 1,2-propylene glycol .solvent, since the glycol
solvent need not be completely removed from the reaction product
prior to use in the finished detergent formulation. Likewise~ khe
formulator of, for example, solid, typically granular, detergent
compositions .may find it convenient to run the process at 30~C~
90C in solvents which comprise alkoxylated, especially ethoxyl~
ated, alcohols, such as the ethoxylated (EO 3-8) C12-C1" alcohols~
such as those available as NEODOL 23 E06.5 (Shell~. When such
ethoxylates are used, it is preferred that they not contain
substantial amounts of unethoxylated alcohol and, most preferably9
not contain substantial amounts of mono-ethoxylated alcohol.
Typically, the industrial scale reaction sequence for
preparing the preferred acyclic polyhydroxy fatty acid amides will
comprise: SteD 1 - preparing the N-alkyl polyhydroxy amine
derivative from the desired sugar or sugar mixture by formation of
an adduct of the N-alkyl amine and the sugar, followed by reaction
with hydrogen:in the presence of a catalysti followed by ~ 2~ ~
reacting the aforesaid polyhydroxy amine wi~h, preferably, a fatty
ester to form an amide bond. While a variety of N-alkyl polyhy
droxy amines useful in Step 2 of the reaction sequence can be
prepared by various art-disclosed processes, the following process
is convenient and makes use of eoonomical sugar syrup as the raw
material. It is to be understood that, for best results when
using such syrup raw materials, the manufacturer should select
syrups that are quite light jR color or, preferably, nearly
colorless ("water-white n ),
: Preparation of N-Alkyl Polyhydroxy Amine
From Plant-Derived Sugar Syrup
I. Adduct Formation - The following is a standard process in
whioh about 420 9 of about 55% glucose solution ~corn syrup -
about 231 g glucose ^ about 1.28 moles) having a Cardner Color of
~ . ... . . . . .
.
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:. . :, ~: , . .. " .; : . .:
.. ., ;.
;
WO 92/08687 i ; PCI~/US91/069
~a!9L25~3 -22-
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less than 1 is re2cted with about 1l9 9 of about 50% aqueous
methylamine ~59.5 9 of methylamine - 1~92 moles) solution. The
methylamine (MMA) solution is purged and shielded with N2 and
cooled to about 10C, or less. The corn syrup is purged and
shielded with N2 at a temperature of about 10~-20-C. The corn
syrup is added slowly to the MMA so1ution at- the indicated
reaction temperature as shown. The Cardner Color is measured at
the indicated approximate times in minutes.
~ . TABLE 1 -
10Time in Minutes: 10 !;. 30 60 12~ 180 ~Q
Reaction TemD. C Gardner Color (AP~roximate)
O
;20
1 1 2 2 4 5
4 6 10 - - -
As can be seen from the above data, the Gardner Color for the
adduct is much worse as the temperature is raised above about 30-C
and at about 50-C~ the time that the adduct has a Gardner Color
below 7 is only about 30 minutes. For longer reaction, and/or
holding times, the temperature should be less than about 20~0O
The Gardner Color should be less than about 7, and preferably less
than about 4 for good color glucamine.
- When one uses lower temperatures for forming the adduct~ the
time"to-reach substantial equilibrium concentration of the adduct.
is shortened by the use of higher ratios of amine to sugar. W~th
the 1.5:1 mole ratio of amine to sugar noted, equilibrium is
reached in about two hours at a reaction temperature of about
30~C. At a 1.2:1 mole ratio, under the same conditions, the time
is at least about three hours. For good color, the co~bination of
amine:sugar ratio; reaction temperature; and reaction time is
selected to achieve substantially equilibrium conversion, e~9O 9
more than about 90%, preferably more than about 95%, even more
preferably more than about 99%, based upon the sugar~ and a color
that is less than about 7, pre~erably less than about 4, more
preferably less than about lj for the adduct.
Using the above process at a reaction temperature of less
than about 20~C and corn syrups with different Gardner Colors as
w O 92/08687- PCT/US9!/06979~ ~
~ ~ 23 - ; 2092563 ~ ~
indicated, the MMA adduct color ~after substantial~ equilibrium is
reached in at least about two hours) is as indicated.
TABLE 2
Gardner Color (ADDroximateL _ !
Corn syrup 1 1 1 1+ 0 0 0~ ¦
Adduct 3 4/5 7/8 7/8 1 2
As can be seen from the above, the starting sugar material
must be very near colorless in order to consistently have adduct
that is acceptable. When ~he sugar has a Gardner Color of about
1, the adduct is sometimes acceptable and sometimes not accept-
able. When the Gardner Color is above 1 the resulting adduct is
unacceptable. The better the initial color of the sugar, the
better is the color of the adduct.
II. Hydroqen Reaction - Adduct from the above having a
&ardner Color of 1 or less is hydrogenated according to the
following procedure.
About 539 9 of adduct in water and about 23.1 9 of United
Catalyst G49B Ni catalyst are added to a one liter autoclave and
purged two times with 200 psig H2 at about 20-C. The H2 pressure
is raised to about 1400 psi and the temperature is raised to about
50~C. The pressure is then raised to about 1600 psig and the
temperature is held at about 50-55~C for about three hours. The
product is about 95% hydrsgenated at this point. The temperature 1 `~
is then raised to about 85-C for about 30 minutes and the reaction
2~ mixture is decanted and the catalyst is filtered out. The
product, after removal of water and MMA by evaporation, is about
95% N-methyl glucamine, a white powder.
~he above procedure is repeated with about 23.1 9 of Raney Ni
catalyst with the ~ollowing changes. The catalyst is washed three
times and the reactor, with the catalyst in the reactor, is purged
- twice with 200 psig H2 and the reactor is pressurized with H2 at
1600 psig for two hours, the pressure is released at one hour and
the reactor is repressurized to 1600 psig. The adduct is then
pumped into the reactor which is at 200 psig and 23-C, and the
reactor is purged with 20D psig H2, etc., as above.
The resulting product in each case is greater than about 95%
N-methyl glucamine; has less than about 10 ppm Ni based upon the
glucamine; and has a solu~ion color of less than about Gardner 2.
-. . . .. . - . .
.. , ;. : ., . . . ~ . .
wO 92/08687 pcrlus91/o6979
~ ~e c ude N-methyl glucamine ;s color stable to about 140'C
for a short exposure time.
It is important to have good adduct that has low sugar
content (less than about 5%, preferably less than about 1%) and a
S good color (less than about 7, preferably less than about 4
Gardner, more preferably less than about 1). i
In another reaction, adduct is prepared starting with about
159 g of about 50% methylamine in water, which is purged and
shielded with N2 at about 10-20-C. About 3:30 9 of about 70% corn
syrup (near water-white) is degassed with N~ at about 50-C and is
added slowly to the methylamine solution at a temperature of less
than about 20-C. ~he solution is mixed for about 30 minutes to
give about 95% adduct that is a very light yellow solution.
About 190 9 of adduct in water and about 9 9 of United
Catalyst G49B Ni catalyst are added to a 200 ml autoclave and
purged three times with H2 at about 20-C. The H2 pressure is
raised to about 200 psi and the temperature is raised to about
50-C. The pressure is raised to 250 psi and the temperature is
~ held at about 50-55-C for about three hours. The product, which
- 20 is about 95% hydrogenated at this point, is then raised to a
temperature of about 85-C for about 30 minutes and the product~
after removal of water and evaporation, is about 95% N-methyl
glucaminet a.white powder. - -
~- It?is~also important to~minimize contact between adduct and
catalyst when the H2 pressure is less than about 1000 psig to
minimize Ni content in the glucamine. The nickel content in the
N-methyl glucamine in this reaotion is about 100 ppm as compared
to the less than 10 ppm in the previous reaction.
~ The following reactions with H2 are run for direct comparison
of reaction temperature effects.
A 200 ml autoclave reactor is used following typical pro-
cedures similar to those set forth above to make adduct and to run
the hydrogen reaction at various temperatures.
Adduct for use in making glucamine is prepared by combining
abou~ 420 9 of about 55% glucose (corn syrup) solution (231 g
glucose; 1.28 moles) lthe solution is made using 99DE corn syrup
from CarGill, the solution having a color less than 6ardner 1) and
about 119 9 of 50% methylamine (59.5 9 MMA; 1.92 moles) (from Air
Products).
,: .... . ~: :,;; . , . .. . ~ . - .
WO 92/08687 ` - PCr/US9~/06~
~ - 25 - 2092~3
~:; .3
The reaction procedure`is as follows~
l. Add about 119 g of the 50% methylamine solution to a N2
purged reactor, shield with N2 and cool down to less than
about 10C.
2. Degas and/or purge the 55% corn syrup solution at 10-20aC
with N2 to remove oxygen in the solution.
3. Slowly add the corn syrup solution to the methylamine
solution and keep the temperature less than about 20'C.
4. Once all corn syrup solution is added in, agitate for about
l-2 hours.
The adduct is used for the hydrogen reaction right after
making, or is stored at low temperature to prevent further
degradation.
The glucamine adduct hydrogen reactions are as follows:
1. Add about 134 9 adduct (color less than about Gardner l) and
about 5.8 9 G49B Ni to a 200 ml autoclave;
2. Purge the reaction mix with about 200 psi H2 twice at about
20-30-C.
3. Pressure with H2 to about 400 psi and raise the temperature
to about 50-C.
4. Raise pressure to about 500 psi 7 react for about 3 hours~
Keep temperature at about 50-55-C. Take Sample 1.
5. Raise temperature to about 85-C for about 30 minutes.
6.` Decant and filter out the Ni catalyst. Take Sample 2.
Sonditions ~or constant temperature reactions:
l. Add about 134 9 adduct and about 5.8 9 G49B Ni to a 200 ml
autoclave.
2. Purge with about 200 psi H2 twice at low temperature.
3. Pressure with H2 to about 400 psi and raise temper~ture to
about 50-C.
4 . Rai se pressure to about 500 psi, react for about 3.5 hours.
Keep temperature at indicated temperature.
5. Decant and filter out the Ni catalyst. Sample 3 is for about
50-55-C; Sample 4 is for about 75C; and Sample 5 is for
about 85-C. ~The reaction time for about 85-C is about 45
minutes.)
All runs give similar purity of N-methyl glucamine (about
94%); the Gardner Colors of the runs are similar right after
. :: , ; , . ........ , . .
,; : "
, : ... .. ~ , ...... .. .
::: . . . .: . -. : ~ :
WO 92/l)g687 PCl /US91/069'7
re ~ ~ ~,5 ~ ~ only the two-stage heat treatment gives good co
stability; and the 85C run gives marginal color immediately aFter
reaction.
EXAMPLE VIII
The preparation of the tallow (hardened) fatty acid amide of
N-methyl maltamine for use in detergent compositions according to
this invention is as ~ollows.
SteD 1 - Reactants: Maltose monohydrate (Aldrich, lot
01318KW); methylamine (40 wt% in water) (Aldrich, lot 03325TM);
Raney nickel, 50% slurry (UAD 5~-73D, Aldrich, lot 12921LW).
The reactants are added to glass liner (250 9 maltose, 428 9
methylamine solution, 100 9 catalyst slurry - 50 9 Raney Ni) and
placed in 3 L rocking autoclave, which is purged with nitrogen
(3X500 psig) and hydrogen (2X500 psig) and rocked under H2 at room
temperature over a weekend at temperatures ranging from 28C to
50-C. The crude reaction mixture is vacuum filtered 2X through a
glass microfiber filter w;th a s;l;ca gel plug. The ~;ltrate ;s
concentrated to a v;scous material. The f;nal traces of water are
azetroped off by dissolving the mater;al in methanol and then
.20 removing the methanol/water on a rotary evaporator. F;nal drying
;s done under high vacuum. The crude product is dissolved in
refluxing methanol, filtered, cooled to recrystallize, filtered
- and the filter cake is dried under vacuum at 35-C. This ;s cut
#1. The f;ltrate is concentrated until a precipitate beglns to
form and is stored in a refrigerator overnight. The solid is
filtered and dried under vacuum. Th;s is cut #2. ~he filtrate is
again concentrated to half~ its volume and a recrystallization is
performed. Very litt-le precipitate forms. A small quantity of
ethanol is added and the solution is left in the freezer over a
weekend. The solid material is filtered and dried under vacuum.
The combined solids comprise N-methyl maltamine which is used in
Step 2 of the overall synthesis.
steD 2 - Reactants: N-methyl maltamine (from Step 1);
hardened tallow methyl esters; sodium methoxide (25% in methanol);
absolute methanol (solvent); mole ratio 1 1 amine:ester; initial
catalyst level 10 mole % (w/r maltamine), raised to 20 mole %;
solvent level-50% (wt.).
W O 92/08687 PCT/US91/06979
~ - 27 - `` ~ ~ ~`2 ~i ~ 3
In a sealed bottle, 20.36 g of the tallow methyl ester is
heated to its melting point (water bath) and loaded into a 250 ml
3-neck round-bottom flask with mechanical stirring. ~he flask is
heated to c~. 70 C to prevent the ester from solidifying.
Separately, 25.0 9 of N-methyl maltamine is combined with 45.36 ~
of methanol, and the resulting slurry is added to the ~allow ester
with good mixing. 1.51 9 of 25% sodium methoxide in ~ethanol is
added. After four hours the reaction mixture has not clarified~
so an additional 10 mole % of catalyst (to a total of 20 mole %)
is added and the reaction is allowed to continue overnight (Cd~
68-C) after which time ~he mixture is clear. The reaction flask
is then modified for distillation. The temperature is increased
to 110C. Distillation at atmospheric pressure is continued for
60 minutes. High vacuum distillation is then begun and continued
for 14 minutes, at which time the product is very thick. The
product is allowed to remain in the reaction flask at 110'0
(external temperature) for 60 minutes. The product is scraped
from the flask and triturated in ethyl ether over a weekendO
Ether is removed on a rotary evaporator and the product is stored
in an oven overnight, and ground to a powder. Any remaining
N-methyl ~altamine is removed from the product using silica gelO
A silica gel slurry in 100% methanol is loaded into a funnel and
washed several times with 100% methanol. A concentrated sample of
the product (20 g in 100 ml of 100% methanol) is loaded onto the
silica gel and eluted several times using vacuum and several
methanol washes. The collected eluant is evaporated to dryness
(rotary evaporator). Any remaining tallow ester is removed by
trituration in ethyl acetate overnight, followed by filtrationO
The filter cake is then vacuum dried overnight. The product is
the t~llowalkyl N-methyl ~altamide.
In an alternate mode, Step 1 of the foregoing reaction
sequence can be conducted using commercial corn syrup comprising
glucose or mixtures of glucose and, typically, 5%~ or higher,
maltose. The resulting polyhydroxy fatty acid amides and mixtures
can be used in any of the detergent compositions herein.
In still another ~ode, Step 2 of the foregoing reaction
sequence can be carried out in 1,2-propylene glycol or NEODOL. At
the discretion of the formulator, the propylene glycol or NEODOL
W O 92/08687 PCT/US91/06979 ~
2~92~ 28 - ~
need not be removed from the reaction product prior to its use to
formulate detergent compositions. Again, according to the desires
of the formulator1 the methoxide catalyst can be neutralized by
citric acid to provide sodium citrate, which can remain in the
polyhydroxy fatty acid amide.
For cleaning compositions where especially high sudsing is
desired (e.g., dishwashing), it is preferred that less than about
5%, more preferably less than about 2%, most preferably no Cl~ or
higher fatty acid be present. Accordingly, preferred polyhydroxy
fatty acid amide compounds and mixtures prepared by the present
invention are preferably substantially free of suds-suppressing
amounts of C~l and higher fatty acids. If some fatty acid is
unavoidably present, commercially-available amine oxide and/or
sulfobetaine (aka "sultaine") surfactants can be used with the
polyhydroxy fatty ac;d amides to at least partially o~ercome some
of the negative sudsing effects. Alternatively, the polyhydroxy
fatty acid amide can be prepared using fatty acid esters primarily
of chain lengths lower than Cl4, especially C,2 fatty methyl
esters.
The polyhydroxy fatty acid amides provided herein are useful
in both solid and liquid detergent compositions, which can also
contain known detersive surfactants, enzymes, builders, soil
release polymers and other detersive adjuncts quite well-known to
the skilled artis~n. ~he formulator ~wishing toj add anionic
optical brighteners to liquid detergents containing relatively
high concentrations (e.g., 10% and greater) of anionic or poly~
anionic substituents such as the polycarboxylate builders may find
it useful to pre-mix the brightener with water and the polyhydroxy
fatty acid amide, and then to add the pre-mix to the final
composition.
It will be apprec;ated by those skilled in the chemical arts
that the preparation of the polyhydroxy fatty ac;d am;des herein
using the di- and higher saccharides such as maltose will result
in the formation of polyhydroxy fatty acid amides wherein l;near
substituent Z is "capped" by a polyhydroxy ring structure. Such
materials are fully contemplated for use herein and do not depart
from the spirit and scope of the invention as disclosed and
claimed.
