Note: Descriptions are shown in the official language in which they were submitted.
~ DIV.
--2--
BACKG_O~ND OF THE INVENTION
1. Field of the Invention
This invention relates to azetidinediones and is more
particularly concerned with novel isocyanato-azetidine-
S diones and particular azetidinedione-isocyanurates and
azetidinedione-urethanes prepared from said isocyanato-
azetidinediones.
2. Description of the Prior Art
-
Various azetidine-2,4-dione compounds have been
described in the art; for typical disclosures of such
compounds see U.S. Patent 3,265,684, Ebnother et al,
Helv~tica Chemica Acta, 42, 1959, pp 918 to 955, and
Martin et al, J. of Organic Chemistry, 36, 1971, pp 2205
to 2210.
I have now discovered what I believe to be a novel
class of isocyanato-azetidinediones defined below. These
compounds possess a degree of stability in the azetidine-
dione ring which allows for their conversion to other
azetidinedione ring containing compounds without the
opening of the ring or polymerization thereof. Such
stability would not have been predictable from the prior
art.
SIJMM~RY OF THE INVENTION
This invention comprises isocyanato-azetidinediones
having the formula (I)
o
R~/\
~\ N X (NCO)y
Rl \f~
O
wherein ~ and Rl when taken individually are independently
selected from the group consisting of hydrogen and hydro-
carbyl, and R and Rl, when taken together with the carbon
atom to which they are attached, represent a cycloalkane
residue having 4 to 6 ring carbon atoms, inclusive, y is
an integer from 1 to 7, and X is a hydrocarbon radical
having a valency of y plu5 one.
The invention also comprises azetidinedione-
--3--
isocyanurates having the formula (II) and azetidinedione~
urethanes having the formula (III)
,0
J II and ( - NHCOO~ R2 III
O ~ I ~` O
A
wherein each A represents the group
1 0
/\
X N- X-
Rl ~
wherein R and Rl have the same signi~icance as set forth
above, R~ is the residue of a hydroxyl compound containing
m hydroxyl groups wherein the value of m is from about 1
to about 8, and X is the divalent form of the hydrocarbon
radical X defined above.
The term "hydrocarbyl" means the monovalent radical
obtained by removing one hydroyen atom from the parent
hydxocarbon having from 1 to 1~ carbon atoms.
Illustrative of hydrocarbyl are alkyl such as methyl,
ethyl, propyl, butyl, pentyl, hexyl, octyl, decyl,
dodecyl, hexadecyl, octadecyl, and the like, including
isomeric forms thereof; alkenyl such as vinyl, allyl,
butenyl, pentenyl, hexenyl, octenyll decenyl, undecenyl r
tridecenyl, hexadecenyl, octadecenyl, and the like,
including isomeric forms thereof; aralkyl such as benzyl,
phenylethyl, phenylpropyl, benzhydryl naphthylmethyl,
and the li~e; aryl such as phenyl, tolyl, xylyl, naphthyl,
biphenylyl, and the like; cycloalkyl such as cyclobutyl,
cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and the
like including isomeric foxms thereof; and cycloalkenyl
such as cyclopentenyl, cyclohexenyl, cycloheptenyl,
cyclooctenyl, a~d the like, including isomeric forms
thereof~
The hydrocarbyl groups which form the groups R and
-4-
Rl can be substituted by one or a plurality of substitu-
ents provided the latter are not reactive with the
azetidinedione ring common to formulae (I), (II), and
(III), the isocyanate groups of (I), the isocyanurate ring
of (II), and urethane linkages of (III). Illustrative of
such substituents are halo, i.e. chloro, bromo, fluoro,
and iodo; nitro; alkoxy from 1 to 8 carbon atoms,
inclusive, such as methoxy, ethoxy, propoxy, butoxy,
pentyloxy, hexyloxy, heptyloxy, octyloxy, and the like,
including isomeric forms thereof; alkylmercapto 'rom 1 to
8 carbon atoms, inclusive, such as methylmercapto, ethyl~
mercapto, propylmercapto, butylmercapto, pentylmercapto,
hexylmercapto, heptylmercapto, octylmercapto, and the
like, including isomeric forms thereof; and cyano.
The term "cycloalkane having 4 to 6 ring carbon
atoms" is inclusive of cyclobutane, 3-methylcyclobutane,
cyclopentane, 3-methylcyclopentane, cyclohexane, 3-methyl-
cyclohexane, 4-methylcyclohexana,and the like.
The term "hydrocarbon radical having a valency of y
plus one" means the divalen~ r trivalent, tetravalent,
pentavalent, hexavalent, heptavalent, and octavalent
radical obtained by removing two, three, four, five, six,
seven or eight hydrogen atoms from the parent hydrocarbon
having a carbon atom content of from 2 to 36, inclusive,
such as alkylene, cycloalkylene, arylene, divalent
radicals having the formula
~r~
wherein V is selected from the group consisting of -CO-,
-O~ SO2-, and alkylene having 1 to 4 carbon atoms,
inclusive, and polymethylene polyphenylene radicals having
the formula
{ ~ CH2 ~--CH2
_5~ 3
wherein z is 0 or a number having an average value from
0 to 1.
DETAILED DESCRIPTION OF THE INVENTION
Isocyanato-Azetidinediones (I)
The novel isocyanato-azetidinediones in accordance
with the present invention are defined by the formula (I)
above. They exhibit good solubility in the common organic
solvents such as ethers, for example, dibutyl ether,
dioxane, and the like; esters, for example, ethyl acetate,
butyl acetate, and the like; ketones, for example,
acetone, methylethyl ketone, and the like; chlorinated
solvents, for example, chloroform, carbon tetrachloride,
and the like; aromatic solvents, for example, benzene,
toluene, xylene, and the like; and dipolar aprotic
solvents, for examplet acetonitrile, dimethylacetamide,
and the like. They are generally less soluble in the low
molecular weight aliphatic and cycloaliphatic hydrocarbons
(pentane, hexane, cyclohexane, and the like).
The compounds (I) are further characterized by strong
absorption in the infrared at from about 1710 cm~l to
about 1745 cm~l and weaker absorption at 1859 cm l due to
the carbonyl groups at the 2 and 4 positions of the
azetidinedione ring, and by strong absorption at about
2275 cm~l due to the isocyanate group(s).
Illustrative but not limiting of the isocyanato-
azetidinediones (I) in accordance with the prese~t
invention are ~-(6-isocyanatohexyl)azetidine 2,4-dione,
N-(6-isocyanatohexyl)-3,3-dimethylazetidine-2,4-dione,
N-(6-isocyanatohexyl)-3,3-diethylazetidine-2,4-dione,
N-(6-isocyanatohexyl)-3-ethyl-3-butylazatidine-2,4-dione,
N-(6-isocyanatohexyl)-3-methyl-3-allylazetidine-2,4-dione,
N-(6-isocyanatohexyl)~3-benzylazetidine~2,4-dione,
N-(6-isocyanatohexyl)-3-phenylazetidine-2,4-dione,
N-(6-isocyanatohexyl)-3,3-pentamethyleneazetidine-2,4-
dione, N-~3-isocyanatocyclopentyl)-3,3 dimethylazetidine-
2,4-dione, N-(4-isocyanatocyclohexyl)-3,3-dimethyl-
azetidine-2,4-dione, N-(4-isocyanatocyclohexyl)-3~ethyl-
3-butylazetidine-2,4-dione, N-(4-isocyanatophenyl)-3,3-
~2 ~ 3
--6--dimethylazetidine-2,4-dione, N~(4-isocyanatophenyl)-3,3
dibutylazetidine-2,4-dione, N-(4-isocyanatophenyl)-3-
ethyl-3-butylazetidine-2,4-dione, N-(3-isocyanato-4-
methylphenyl)-3,3-dimethylazet:idine-2,4-dione,
N-(3-isocyanato-4-methylphenyl)-3,3 diethylazetidine-2,4-
dione, N-(3-isocyanato-4-methylphenyl)-3-ethyl 3-butyl-
azetidine-2,4-dione, ~-(3-isocyanato-6-methylphenyl)-3,3
dimethylazetidine-2,4-dione, N (3-isocyanato~6-methyl-
phenyl)-3 ethyl-3-butylazetidine-2,4-dione, N-(2-methyl
3-isocyanatophenyl)-3,3-dimethylazetidine-2,4-dione,
N-~2 methyl-3-isocyanatophenyl)-3,3-diethylazetidine-
2,4-dione, N-(2-methyl-3-isocyanatophenyl)-3-ethyl-3-
butylazetidine-2,4-dione, 4-isocyanato-4'-~3,3-dimethyl-
2,4-dioxo-azetidino)diphenylmethane, 4-isocyanato-4'-
(3,3~diethyl-2,4-dioxo-azetidino)diphenylmethane,
4-isocyanato-4'-(3,3-dipropyl-2,4~dioxo-azetidino)diphenyl-
methane, 4-isocyanato-4'-(3-ethyl-3-butyl-2,4-dioxo-
azetidino)diphenylmethane, 4-isocyanato-4'-(3-benzyl-2,4-
dioxo-azetidino)diphenylmethane, 4-isocyanato-4'-(3-
phenyl-2,4-dioxo-azetidino)diphenylmethane, 4-isocyanato-
4'-(3,3-pentamethylene-2,4-dioxo~azetidino)diphenyl-
methane, and the like; and the polyisocyanato-azetidine-
diones wherein the equivalent of about one isocyanate
group in triphenylmethane-4,4',4" -triisocyanate,
1,6~ undecane triisocyanate, or a polymethylene poly-
phenyl polyisocyanate having an equivalent weight of about
130 to about 160, is replaced by a 3,3-dimethyl-,
3,3-diethyl-, or 3-ethyl-3-butyl-2,4-dioxo-azetidino
radical.
The isocyanato-azetidinediones are prepared by
processes which are analogous to those known in the art.
Illustratively, the compounds can be prepared using a
procedure analogous to that set ~orth in U.S~ Patent
3,265,684, cited supra, according to the following
equation:
H O
R ¦ ¦¦ tert.amine
f,C-C-Cl + X(NC0) ~ tert~amine.HCl
Rl Y solvent
IV V
The acid chloride (bromide, iodide, or fluoride can
also be used) starting materials (IV) are well known and
readily available compounds wherein R and Rl have the
significance set forth above.
The isocyanate reactants (V) wherein X and y have the
same significance as set forth above can be any of the
known polyfunctional organic isocyanates. A preferred
group of the polyisocyanates which can be employed are
hexamethylene diisocyanate; 1,4-cyclohexylene diisocyanate,
methylenebis(cyclohexyl isocyanate)~ isophorone diiso-
cyanate; methylenPbis(phenyl isocyanate) including the
4,4'- and 2,4'-isomers and mixtures thereof, m- and p-
phenylene diisocyanates, 2-chloro-p-phenylene diisocyanate,
2,4- and 2,6-toluene diisocyanate and mixtures thereof,
1,5-naphthalene diisocyanate, 1,6,11-undecane triiso-
cyanate, triphenylmethane~4,4',4" -triisocyanate,
the liquefied forms o methylenebis(phenyl isocyanate)
such as those described in U.S. 3,384,653; and the
polymethylene polyphenyl polyisocyanates.
The proportions in which the acid halide (IV) and
isocyanate (V) are reacted ~ogether are not critical but
are preferably about equimolar, and, most preferably the
isocyanate is employed in up to 100 percent mole excess
o~er the acid halide concentration~
The reaction is carried out by heating the reactants
together in an inert organic solvent at a temperature of
at least about 75C in the presence of an acid halide
acceptor, preferably, a tertiary organic amine such as
triethyl amine, tributyl amine, pyridine, and the like.
The term "inert organic solvent" means an organic solvent
which does not interact with the reactants or the product
or otherwise interfere with the reaction. Illustra~ive
of the solvents which can be employed are the solvents
-8-
set forth above in which the products are soluble.
The progress and completion of the reaction can be
easily monitored by sonventional analytical procedures
such as by infrared spectroscopy, nuclear magnetic
resonance spectroscop~, and like analytical methods.
Generally speaking, the hydrohalide salt or the
tertiary amine precipitates frcm solution and is readlly
removed by filtra~ion. The solvent is removed by standard
methods such as distillation either at atmospheric or
reduced pressure to yield the product. The latter can be
purified, if desired, by routine procedures such as
distillation and/or recrystallization, chromatography
and the like.
The compounds of formula (I) all possess the property
of forming highly useful polyamide-polyurea copolymers
when polymerized with orsanic polyamines. The isocyanate
groups react with the amine function in the well known
manner to form the urea linkages. The amide linkages are
formed from the facile opening of the azetidinedione ring
by the amine. Accordingly, typical copolymers are formed
in accordance with the following representative schematic
equation wherein the compound (I) is a monoisocyanate
~Ia) and the polyamine is a diamine,
r O O 0~
Ia ~ (NH2 )2 B ~ LNHBNHC--CRRl--CNHXNHC~
wherein B is the organic residue of the polyamine.
It will be understood by one skilled in the art that
the above equation and recurring unit produced thereby
are illustrative only o the linear types o~ polymers
that can be prepared. When y in (I) is greatex than 1
and/or the polyamine has a functionality greater than 2
then cross-linked polymers will result.
The polymerization process can be carried out using
any prior art methods for reacting polyamines with poly-
isocyanates to prepaxe polyureas. For example, see ~.S.
Patents 4,296,212; 4,374,210 and 4,433,067 for typical
reactants and pxocedures.
g
The copolymers can be prepared in bulk, cast, or
molded form depending on the end-use desired, the presence
or absence of other ingredients, anc1 the like.
Generally speaking, the compound (I) and the poly-
amine are polymerized in substantially equivalent amounts
wherein the term "e~uivalent" in reference to both
reactants refexs to their molecular weights divided by
their respective functionalities. The term
"functionality" in reference to the polyamines i5 simply
the number of amine groups whereas in reference to (I)
the aæetidinedione ring serves as one functional group
while the isocyanate(s) serves as the other funtional
group(s).
Illustratively, the organic polyamines can have an
amine functionality of from 2 to 6 and a molecular weight
of from about 60 to about 5000; such as ethylene diamine,
butylene diamine, amine terminated polyether polyols
havin~ 2 or 3 primary or secondary amine groups and a
molecular weight of from about 1000 to about 4000.
Mcst useful of the polyamide-polyurea copolymers are
the linear ones prepared ~rom the difunctional compounds
(Ia) and the organic diamines.
The polyamide-polyuxea copolymers can be rapidly
molded to form auto parts such 2S bumpers, body elements,
panels, doors, engine hoods, skirts, air-scoops, and
the like.
Also the compounds ~I) in accordance with the
present ir.vention are use~ul as acid and water scavenging
agentC for stabilizing various kinds of halogenated
polymer systems such as chlorinated polymers and
particularly polyvinyl chloride. The monoisocyanates
(Ia) àre particularly useful for the preparation of the
novel azetidinedione-isocyanurates (II) and azetidine-
dione-urethanes (III) discussed below.
10-
~-" i~nr~d~r~ o urates (II)
1
R ~
3 X N~ X NCO ~ II
R~ ~
bl Ia
The novel azetidinedione-isocyanurates (II) in
accordance with the present invention are obtained via
the trimerization of the monoisocyanato-azetidinediones
(Ia) as set forth in the above reaction scheme wherein X,
R, and Rl are defined above.
The azetidinedione-isocyanurate compounds can be used
as acid scavenging agents for stabilizing the same types
of halogenated polymer systems referred to above.
The preferred class of monoisocyanates (Ia) for the
trimeriæation to (II) is the one wherein X is a divalent
hydrocarbon radical, and, particularly, an arylene radical
or a radical having the formula
2~ . ~ V ~
defined above and R and Rl are the same or different alkyl
groups.
Illustrative but not limiting of the monolsocyanates
which are readily trimerized to the isocyanurates (II)
are the monoisocyanate-az~tidinediones ~xemplified above.
Preferred species for the trimerization to (II) are
those monoisocyanates exemplified above wherein X is
4-methylphenylene, 6-methylphenylene, and mixtures thereof,
and 4,4'-methylenebisphenylene.
Th~ trimerization process is carried out using any
of the methods and techniqùes well known to those skilled
in the art; for illustrative methods see Saunders and
Frisch, Polyurethanes Chemistry and Technology, Part I,
1962, pp 94 to 95, Interscience Publishers, New York,
N.Y., and U.S. Patents 2,979,485; 2,993,870 and 3,381,008.
~6~
--11
The trimerization is preferabl~ carried out in the
pre~ence of an inert solvent, i.e. a solvent that does not
react with i~ocyanate groups or otherwise interfere with
the course of the trimerization. Preferred solvents are
aromatic solvents such as benzene, toluene, xylene, nitro-
benzene, chlorobenzene and the like, and aliphatic esters
such as ethyl acetate, butyl acetate, and the like.
Advantageously, the trimerization is carried out at
a temperature falling within a range of about 50C to
about 200C, preferably about 75C to about 150C and in
the presence of a trimerization catalyst.
Any of the catalysts known in the art for the trimer-
ization of isocyanates may be employed. Typical are those
disclosed in the following: The Journal of Cellular
Plastics, November/December 1975, p 329; U.S. Patent Nos.
3,745,133; 3,896,052, 3,899,443; 3,903,018; 3,954,684
and 4 r 126,742, and mixtures of any of the catalysts
disclosed therein.
A preferred group of ca~alysts comprises the alkali
metal salts of lower alkanoic acids such as the sodium,
potassium, or lithium salts of formic acid, acetic acid,
propionic acid, butyric acid, heptanoic acid, 2~methyl-
hexanoic acid, 2~ethylhexanoic acid, and the like.
The catalyst concentration is not critical, and,
advantageously, falls within a range of from about 0.1
part to about 10 parts by weight per equivalent of
isocyanate.
Surprisingly, the azetidinedione ring remains stable
under the conditions of the trimerization process ~hich
includes high temperatures (as high as 170C) while in
the presence of the strongly basic trimerization
catalysts. This is highly unexpected as the azetidine-
dione ring is known to open readily under basic conditions.
Also/ the closely related ~-lactams (azetidinones) readily
ring-open and polymeri~e under mild basic conditions
because of the steric strain in a 4-membered ring.
Certain trimerization catalysts, such as the very strongly
~2~;~C~
basic ones like potassium tertiary butoxide and sodium
methoxide, do tend to cause some ri~g decomposition during
trimerization. However, the majority of the trimerization
catalysts provide the desired products.
Generally speaking, the isocyanurate products are
solids and are easily isolated from their reaction
solutions by removing the solvent using known methods.
Azetidinedione-urethanes tIII)
Ia + R2(OH)m
The novel azetidine-urethanes (III) in accordance
with the present invention are obtained via the reaction
of the monoisocyanato-azetidinediones (Ia) deflned above
with the hydroxyl compounds defined by the formula
R2(OH)m as shown in the equation set forth above and using
the appropriate stoichiometric proportions of the
isocyanate to rPact with substantially all of the hydroxyl
functionality. Any of the well known procedures in the
art for reacting isocyanate compounds with hydroxyl
containing compounds to form urethanes and polyurethanes,
either with or without solvent, can be employed in
preparing the compounds (III) in accordance with the
present invention. For detailed methods and illustrative
techni~ues for urethane preparation see Saunders and
Frisch, Polyurethanes Chemistry and Technology, Part I
cited supra and also Part II of the same series.
The hydroxyl compounds which can be employed include
any o~ the primary and secondary hydroxyl containing
compounds having a MW from about 32 to about 5000 such as
the aliphatic, aromatic and cycloaliphatic mono~alcohols
and organic polyols having a functionality of from 2 to 8.
Typical mono-alcohols but not limiting thereof are
methanol, ethanol, butanol, phenol, cyclohexanol, and
the like.
Of the organic polyols the functionality is
preferably from 2 to 3, and most preferably 2. A
preferred molecular weight range is from about 60 to
about 3000.
A preferred class of polyhydric alcohols are the low
-13-
molecular weight alkylene glycols, i.e., ethylene glycol,
1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol,
diethylene glycol, and the like; and the polyalkyleneoxy
glycols of MW range of about 200 to abou-t 2000 such as
polyethyleneoxy glycols, polypropyleneoxy glycols,
polyethyleneoxy-polypropyleneoxy glycols, and polytetra-
methyleneoxy glycols.
Surprisingly, even at elevated reaction temperatures
and in the presence of urethane catalysts, the azetidine-
dione ring remains stable to the hydroxyl groups of thepolyol component and does not polymerize with them.
The products are characterized by strong infrared
absorption at about 1740 cm~l and weaker absorptions at
1850 cm~l due to the azetidinedione rings.
The urethane products range from viscous li~uids to
solids (both crystalline and amorphous) depending largely
on the molecular weight and functionality of the polyol
employed. If the preparation is carried out in the
absence of solvent the pxoduct can be obtained directly.
Otherwise the products are easily isolated from their
reaction solutions using known methods.
The compounds of formula (III) wherein m is greater
than one, similarly to those of (I) discussed above,
react readily with organic polyamines, and, in this case,
to form highly useful polyamide--polyurethane copolymers.
Again, for ease of illustration only, the following
schematic equation sets forth the linear copolymer
recurring unit obtained from the polymerization of a
compound (III) wherein m = 2 with an organic diamine.
III (m = 2) + (NH2)2B
r O O O O O O~
11 11 11 11 11 11
~HBNHC CRR 1 CNHXNHCOR2 OCNHXNHC--CRR 1 C--_
The polyamine has the same significance discussed
above and the same preparative procedures and teaching
referred to above for the polyamide-polyureas applies to
o~
the preparation of the polyamide-polyurethanes. In
respect of the equlvalent weight of the compound (III~ lt
refers to the molecular weight of the compound dlvided
by its number of azetidinedione rings which latter
S represent functional groups.
Most uceful of the polyamide-polyurethanes are the
linear ones.
The polyamide-polyurethanes can be molded to form
the same types of auto parts described above for the
10 polyamide-polyureas.
The compounds (III) wherein m equals one are useful
as acid scavenging agents for the stabilization of
halogenated polymers.
The following examples describe the manner and
process of making and using the ivention and set forth
the best mode contemplated by the inventor of carrying
out the invention but are not to be construed as limiting~
Exa~le 1
A 2 liter three-necked reaction flask equipped with
a stirrer, reflux condenser, thermometer, addition funnel,
and gas inlet tube was charged with a solution of 105 g.
~0.6 mole) of 2,4-toluene diisocyanate and 45 g. (0.42
mole) of isobutyryl chloride dissolved in 500 ml. of
xylene. The solution was stirred and heated in an oil
bath to a temperature of 115 to 120C.
A solution of 65 g. (0.64 mole~ of triethylamine
dissolved in 50 ml. of xylene was added dropwise to the
reaction solution through the addition funnel and under
a nitrogen atmosphere over a 4 hour period. Heating of
the stirred solution was continued for a further 3 hour
period. The solution was cooled to about 0C and the
precipitated solid of triethylamine hydrochloride was
separated by filtration. The filter cake was washed with
fresh xylene and these washings added to the filtrate.
The filtrate and washings were distilled to remove
the solvent using a rotary evaporator under a pressure
of about 15 mm. of mercury and a tempexature of about
70C. An oily residue was obtained. The oil was vacuum
)03
-15-
distilled using a short Vigreux column under a pressure of
0.08 mm. of mercury. The first fraction, b.p.= 6C~120Cr
wt. = 41.4 g., was a 39 percent recovery of starting
2,4 toluene diisocyanate; the second fraction, b.p. =
120-145C., wt. = 63.1 g. solidified on standing,
m.p. = 58~to 70C. Recrystallization of the latter
product from 50 ml. o~ cyclohexane provided 44.2 g. of
crystalline solid, m.p, =71-80C representing a 45
percent yield of an isocyanato-azetidinedione mixture
of the two isomeric compounds (a) N-(3-isocyanato-4-
methylphenyl)-3,3-dimethylazetidine-2,4-dione and (b)
N-(3-isocyanato-6-methylphenyl)-3l3-dimethylazetidine-
2,4-dione in accordance with the present invention and
having the formulae
1 5
CH 3 CH3 ~ CH3
~ and~ N ~ CH3
/N\ NCO
O=<' >=O
(b)
CH3 CH3
(a)
The NMR integration showed that the proportion of
isomer ~a) to isomer (b) in the reaction product was
60/40 respectively. The isomer (a) was separated by
repeated recrystallization from cyclohexane with (a)
having the higher m.p. = 89C.
Elemental analysis for isomer (a): Calculated for
Cl3Hl2N2O3: C = 53.93%, H = 4.95%, N - 11.47~; Found:
C = 63.84%, H = 5.08%, N = 11.31%.
Infrared for mixture of (a) and (b) (CCl4) (in cm~l):
2960, 2910, 2275(s), 1859, 1741(s), 1605, 1512, 1390 (9),
1375, and 1040.
Proton nuclear magnetic resonance for isomer (a) (CDCl 3 ):
~ 7.52 (multiplet, 2 protons), 7.00 7.28 (m,l) 7.34
~'~6~ 3
-16-
(singlet,3), 2.36 (s, 3), 1.50 and 1.45 (s,6).
Example 2
-
Using a slmilar procedure and apparatus as descri~ed
in Example 1 except on a smaller scale, a stirred solution
of 17.5 gO (0.1 mole) of 2,4-toluene diisocyanate and
20.0 g. (0.15 mole) of a-ethylbutyryl chloride dissolved
in 125 ml. of xylene was heated ~o about 120C.
Over a 6 hour period a solution of 21 g. (0.21 mole)
of triethylamine dissolved in 10 ml. of xylene was added
to the stirred solution at the above temperature. The
solution was stirred and heated at 140~C overnight (about
15 hours). The cooled solution (about 0C) was filtered
to remove the solid triethylamine hydrochloride which was
washed with fresh xylene and the washings added to the
filtrate.
The solvent was removed from the combined filtrate
and washings in a rotary evaporator at about 15 mm. of
mercury pressure and a temperature of 70C. An oily
residue of wt. = 34.3 g. remained. It was vacuum
distilled using the apparatus described in Example 1
and under a pressure of 0.05 mm. of mercury. The first
fraction, b.p. = 65 to 70C, wt. = 3.2 g. was an 18
percent recovery of the starting 2,4-toluene diisocyanate.
The second fraction had a b.p. - 145- 150C, (wt.= 9.5 g.)
and was recovered as an oil rep.resenting a 35 percent
yield of an isocyanato-azetidinedione mixture of the two
isomers (a~ N-(3-isocyanato-4-methylphenyl)-3,3-diethyl-
azetidine-2,4 dione and (b) N-(3-isocyanato-6-methyl-
phenyl)-3,3-diethylazetidine-2,4-dione in accordance with
the present invention and having the formulae
--17--
o
~3~NCO CH~ ~><C H
~N~ NCO
O=< >--O
\,,/ ( b )
/\
C2Hs C2Hs
(a)
Infrared for the mixture (Neat) (in cm~l): 2952, 2915,
2860, ~255(s), 1861, 1840, 173~(s), 1600t 1570, 1510,
1455, 1380, 1040.
Proton NMR for the mixture (CDCl3): 3 7.65 (m,l), 7.40 -
7.18 (m,2), 2040 (SJ3) ~ 1.86 (m,4), 1.13 (m,6).
The relative proportions of (a) to (b) in the
mixture could not be determined with the same precision
as in the previous Example 1 because of the more complex
reso~ance of the ethyl groups.. However, isomer (a) was
assumed to be in excess because of lower steric hindrance
in ~a~ as opposed to (b).
Example _
Using a similar procedure and apparatus as described
in Example 1, a stirred solution o 52.0 g. (0.3 mole)
of 2t4-toluene diisocyanate and 25 g. (0.15 mole) of
2-ethylhexanoyl chloride dissolved in 450 ml. of xylene
was heated to 138 to 145C.
Over a period of 4 to 5 hours a solution of 30.0 g.
30 (0.3 mole) of triethylamine dissolved in 20 ml. of xylene
was added to the stirred solution at the above temper-
ature. The solution was stirred and heated within the
above temperature range for an additional 2 hour period~
The solution was cooled to about 0C and the precipitated
triethylamine hydrochloride was removed by filtration.
The precipitate was washed with fresh xylene which was
added to the filtrate.
The solvent was removed ~rom the combined filtrate
-18-
and washinys in a rotary evaporator at about 15 mm.of mer
cury pressure and a temperature of 70C. ~n olly residue,
wt. = 84.1 g~ was obtained. The residue was distilled
using the apparatus described in Example 1 and under a
pressure of Ool mm. of mercury. The first fraction,
b~p. - 60 to 110C, wt. = 3207 g. was a 63 percent
recovery of the starting 2,~-toluene diisocyanate. The
second fraction, b.p. = 130 to 160C, wt. = 34.2 g., was
isolated as an oil and represented a 76 percent yield of
an isocyanato-azetidinedione mixture of the two isomers
(a) N-(3-isocyanato-4~methylphenyl)-3-ethyl-3-butyl-
aæetidine~2,4-dione and (b) N-(3-isocyanato-6-methyl-
phenyl)-3-ethyl-3-butylazetidine-2,4-dione in accordance
with the present invention and having the formulae
0
CH3 CH3
~ and ~ ~ C~Hs
/N~ NC0
O _< >= O
~ ~b)
/\
C2Hs C4Hs
(a)
Infrared for the mixture (CC14) (in cm~l): 2g60, 2940,
2865, 2275(s), 1862, 1740(s), 1613, 1580, 1520, 1460,
1382.
Proton NMR for the mixture (CDCl3): ~ 7.60 (m,l), 6.90 -
3~ 7.20 (m,2), 2.38(s~3), ~ 2.10 - 0.90 (m,14).
Elemental analysis for the mixture: Calculated for
C~,H20N20~: C = 67.98%, H = 6.71~, N = 9.33%; Found:
C 68.02~, H = 6.54%, N = 9.42%.
Similarly to Example 2 above, the relative propor-
tions of (a) to (b) in the mixture could not be det~rmined
with precision but isomer (a) was assumed to be the major
component.
19-
Example 4
-
Using a similar procedure and apparatus as described
in the previous e.xamples, a stirred solution of 50 g~
(0.2 mole) of 4,4'~methylenebis(phenyl isocyanate) and
16 g. (0.15 mole) of isobutyryl chloride dissolved in
250 ml. of xylene was heated to about 120C.
Over a 3 hour period a solution of 25 g. (0.25 mole)
of triethylamine dissolved in 20 ml. of xylene was added
to the stirred solution at the above temperature. The
heating and stirrins wa~ continued for a further 3 hour
period. The solution was cooled to about 0C and ~he
solid triethylamine hydrochloride was removed by
filtration and washed with fresh xylene which latter
was added to the filtrate.
The solvent was removed from the combined filtrate
and washings in a ro~ary evaporator at about 15 mm. of
mercury pressure and a temperature of 70C. A solid
residue was obtained, wt. = 55.1 g. This residue was
recrystallized from 80 ml. of cyclohexane to provide
13.3 g. of crystalline solid, m.p. = 100C representing
a 27 percent yield of 4~isocyanato-4'-(3,3-dimethyl-
2,4-dioxo-azetidino)diphenylmethane in accordance with
the present invention and having the formula
o
CH~CI ~ CH 2 ~ NCO
o
Elemental analysis: Calculated for ClgHl6N2O3:
C - 71.24%t H a 5.02~, N = 8.74%; Found: C = 71.76%,
H = 4.67~, N = 8.87%.
Infrared (CC14) (in cm 1): 2955, 2910, 2255(s), 1852,
1743(s), 1601, 1512(s), 1390, 1368.
Proton NMR (CDCl3): ~ 7.71 (d,2), 7.14 (d,2), 7.02 (s,4),
3.93 (s,2), 1.46 (s,6).
-20-
ExamE~le S
Using a similar procedure and apparatus as described
in the previous examples a stirred solution of 20 g.
(0.12 mole) of hexamethylene diisocyanate and 30 g. (0.28
S mole) of isobutyryl chloride dlssolved in 150 ml. of
xylene was heated to about 120C.
Over an 8 hour period a solution of 35 g. (0.34 mole)
of triethylamine dissolved in 30 ml. of xylene was added
to the stirred solution at the above temperature. The
heating and stirring was continued overnight (about 16
hours). After about 24 hours of heating, the reaction
solution was cooled to about 0C and the precipitated
triethylamine hydrochloride was removed by iltration
and washed with fresh xylene which was combined with the
filtrate.
The solvent was removed from the combined filtrate
and washings in a rotary evaporator at about 15 mm. of
mercury pressure and a temperature of 80C. A residue
of an oil remained which was vacuum distilled using the
apparatus described in Example 1 and under a pressure of
0.1 mm. of mercury. A fore-fraction had a b.p. = 50 -
85C. The main fraction had a b.p. = 115-120C and
wt. = 6.5 g. and remained a liquid representing a 22
percent yield of N-(6-isocyanatohexyl)-3,3-dimethyl-
azetidine-2,4~dione in accordance with the present
invention and having the formula
o
CH3 ~
~ N-~CH2~-NCO
CH3
Infrared tNeat) (in cm~l): 2920, 2850, 2255(s), 1721(s),
1450, 1435~ 1390, 1350, 1250.
Proton NMR (CDC13): ~ 3.32 (4,~), 2.0 - 1.0 (8,m),
1.38 (~,s).
~ ~O ~`33
-21-
Example 6
Using a similar procedure csnd apparatus as described
in the previous examples, a stirred solution consisting
of 14.5 g. (0.106 eq.) of a polymethylene polyphenyl poly
isocyanate mixture (isocyanate equiv.=137) containing
about 40 to 45 percent by weight of methylenebis(phenyl
isocyanate) and the remainder of said mixture consisting
of polymethylene polyphenyl polyisocyanates having a
functionality greater than 2, and 8.2 g. (0.05 mole) of
2-ekhylhexanoyl chloride dissolved in 100 ml. of xylene
was stirred and heated to 140C.
Over a 2.5 hour period a solution of 7.5 g. (0.075
mole) of triethsylamine dissolved in 20 ml. of xylene was
added to the stirred solution at the above temperature.
Stirring of the solution at 140C was continued for
another 6 hours during which time the progress of the
reaction was followed by infrared analysis on aliquot
samples. The characteristic acid chloride absorption at
1785 cm~l disappeared and the two characteristic
absorptions at 1740 arsd 1845 cm~l due to the azetidine-
2,4-dione ring increased during the reaction period.
The reaction solution was cooled to about 0C and
the precipitated triethylamine hydrochloride was removed
by ~iltration. The filtrate was heated in a rotary
evaporator at about 10 mm. of mercury pressure followed
by higher vacuum (about 0.15 mm.) to remove all the
solvent. An oily residue, wt. - 21.8 g. was obtained;
inirared analysis showed the characteristic azetidinedione
absorption at 1740 and 1845 cm~~; isocyanate equiv. wt.
294 (theor.=267). This residue represenked a 97 percent
yield of an isocyanato-azekidinedione in accordance with
the present invention having khe representative formula
C2Hs ~ NCO 1 NCO
~ N ~ CH ~ CH 2 ~
o -- z=average value of about 0.8.
'~6~
-22-
Example 7
A 250 ml. reaction flask equipped with a magnetic
stirrer, reflux condenser, and thermometer was charged
with 25.0 g~ (0.10 mole) of the isocyanato-azetidinedione
mixture prepared in accordance with Example 1 above,
0.15 g. of a trimerization catalyst comprising about 67
percent by weight of potassium 2-ethylhexanoate dissolved
in a polypropylene glycol of about 400 MW, and 32 ml. of
ethyl acetate~
The solution was stirred and heated under reflux
(reaction temperature of about 80C). Aliquot samples
were removed periodically for infrared spectrum analysis
to determine the progress of the trimerization of the
isocyanate groups, i.e. their disappearance. After 12
hours the reaction was terminated as the isocyanate was
totally consumed.
The reaction solution was poured into 150 ml. of
ethyl acetate and washed with water in a separatory funnel
to remove the catalyst from the product which latter
remained in the organic solution. The organic layer was
dried by storage over magnesium sulfate. The solution
was filtered to remove the magnesium sulfate and was then
heated in a rotary evaporator under about 15 mm. of
mercury pressure to remove the ethyl acetate. The residue
was a yellow colored resinous fluid when warm and which
was dried further under 10 mm. of mercury pressure and
60C. The product solidified to an amber colored
resinous solid which was pulverized to pale yellow powder,
wt. = 24.5 g., melted at 200 to 260Ç representing a 98
percent yield of an azetidinedione-isocyanurate mixture
in accordance with the present invention and represented
by the formula
o
A ~ A
-N ~I~
0~2~ J~o
A
.~6~
-23-
wherein ~ _ H3C ~ , CH3 and ~ H3/ o
N ~ CH3 N ~ CCH3
O O
and mixtuxes of these groups in the same molecule.
Elemental analysis: Calculated for C39H3~N609:
C = 63~93%, H = 4.95~, N = 11.47%; Found: C = 63.58%,
H = 5.38%, N ~ 11.17%.
Infrared (CC14) (in cm~l): 3015, 2975, 2930, 2865, 1860,
1745(s), 1718(s), lSll, 1405, 1140, 1050.
~ hen the same reactants as above but in smaller
proportions (4.8 g. of the isocyanato-azetidinedione and
lS 0.12 g. o~ the trimerization catalyst mixture) were
reacted in 10 ml. of xylene at a temperature of about
120C the reaction was completed in 4 hours. The same
solid resinous product was obtained.
Example 8
Using the same apparatus and procedure set forth in
Example 7 above, a 5.0 g. sample (0.02 mole) of the
isocyanato-azetidinedione mixture prepared in accordance
with Example 3 above was stirred and heated under reflux
with 0~12 g. of the same trimerization catalyst used in
Example 7 in 15 ml. of ethyl acetate.
After 18 hours the trimerization was complete as no
more isocyanate absorption could be observed by infrared
analysis. The solution was diluted to 50 ml. of ethyl
acetate and washed with three separate portions of water
in a separatory funnel. The organic layer was separated
and dried over magnesium sulfate. After separating the
drying agent the solution was stripped of solvent in a
`' rotary evaporator und`er 10 mm. of mercury pressure.
The residue was a resinous yellow solid which was easily
pulverized (wt.-4u92 g.) and melted at 145 to 160C
representing a 98 percent yield o~ an azetidinedione-
isocyanurate mixture in accordance with the present
invention and represented by the formula
~2~ )3
-24-
o
A ~ ,A
~N N'
o = ~N J o
A
wherein A = H3C ~ o
~ ~ ~ C4Hg
10ll ~ CH3
and ~ ~ C~Hs
~ C4Hg
O
and mixtures of these groups in the same molecule.
Infrared ~CHC13) (in cm ~): 3020, 2965, 2945, 2875, 1860,
1742(s), 1720(s), 1511, 1417(s), 1220, 1050.
Example 9
-
The following experiment describes the preparation
of a bis urethane in accordance with the presen~
invention.
A 100 m~. reaction flask equipped with a magnetic
stirrer, condenser, and thermometer was charged with 5.0 g.
(0.02 mole) of an isocyanato-azetidinedione mixture
prepared in accordance with Example 1 above, 20.25 g.
(0.01 mole) of a polyoxypropylene glycol having a
molecular weight of about 2025, and about 0.035 g. of
dibutyl tin dilaurate (0.2 drop).
The mixture was heated at 90 to 95C for about
18 hours and resulted in a cloudy viscous liquid.
Infrared analysis showed that all of the isocyanate was
consumed and the absorptions at 1850 and 1740 cm~l due to
the azetidinedione ring remained intact. Gel permeation
chromatography (GPC) in tetxahydrofuran solvent showed a
single peak constituting greater than 95 percent by
weight of the product mixture. Thus there was obtained
a bis urethane havillg the representative formula
- 2 5 ~ 6~ 33
CH3 CH~
CH 3~ NHCOO-CH2 -CH - _~n = ~. CH 3
about 35
-S?= =S~-
CH3 CH3 CEI3 CH3
Using the same procedure and apparatus described
above, 6.0 (0.02 mole) of an isocyanato-azetidinedione
mixture prepared in accordance with Example 3 above,
20.23 g. ~0.01 mole) of the same polyoxypropylene glycol
as above, and 0.12 g. of dibutyl tin dilaurate were
heated at 95-100C for about 18 hours.
Infrared analysis of the resulting cleax viscous
liquid showed complete consumption of isocyanate and the
azetidinedione ring intact at 1860 and 1745 cm~l. GPC
analysis showed a single peak amounting to greater than
96 percent by weight of the product mixture.
Thus there was obtained a bis urethane in accordance
with the present invention having the formula
25 CH3 ~--NHCOO-CH2 -CH~CH2C~ OOCNH~ CH 3
about 35 T
-~?= -S~=
CzMs C4Hs CzHs C4Hs
Example 10
A 100 ml~ reaction flask equipped similarly to the
one described in Example 9 was charged with 0.45 g.
3S (0.005 mole) o~ 1,4-butanediol, 5 g. (0.01 mole) of an
isocyanato-azetidinedione mixture prepared in accordance
with Example 1, 0.1 g~ of dibutyl tln dilaurate, and
10 ml. of ethyl acetate.
-2~-
The mixture was stirred ancl heated at 80 to 90C for
about 24 hours. Upon cooling a precipitate formed and
was collected on a suction filter, washed with fresh ethyl
acetate and thoroughly dried; wt. = 1.45 g., m.p. a 220
to 222C.
Thus there was obtained a bis urethane in accordance
with the present invention having the formula
CH3 ~ NHCOO-~CH2t~-OOCNH ~ CH 3
='~?- =S~
CH3 CH3 CH3 CH3
Infrared (CHCl3) (in c~ 3450, 3016, 2975, 1860, 1744,
1590, 1535, 1485, 1460, 1400, 1378, 1060.
Proton NMR (CDC13): ~ 7.50-7.0 (m,6), 6.45 (s,2), 4.20
(t,4)l 2.17 (s,6), 1.74 (t,4), 1.40 (s,12).
Elemental analysis: Calculated for C30H34N4O8:
C = 62.22~, H = 5.92%, N = 9.68~; Found: C = 62.12~,
H = 6.12%, N = 9.63~.
Example _
A 100 ml. reaction flask equipped according to
Example 9 was charged with 0.90 g. (0.007 mole) of
trimethylolpropane, 6.0 g. (0.02 mole) of an isocyanato-
azetidinedione mixture pxepared in accordance with
Example 3 above, 0.1 g. of dibutyl tin dilaurate, and
10 ml. of ethyl acetate.
The mixture was stirred and heated at 80 to 90C
for about 24 hours. No precipitate formed upon cooling
the reaction solution. The solvent was removed using a
rotary evaporator under about 10 mm of mercury pressure
to yield a resinous solid; m.p. greater than 70C.
Thus there was obtained a tris urethane in accor-
dance with the present invention having the formula
-27-
CH 3 ~ NHC()OCH2~l CC2Hs
L~
C2Hs C4~9 3
Infrared (C~Cl3) ~in cm 1) 3430, 3018, 2970, 2940, 2875t
1855, 1740(s), 1620, 1590, 1530, 1460, 1391.
Elemental analysis: Calculated for Cs7H74N6ol2:
C = 66 13%, H = 7.21~, N = 8.12%; Found: C = 66.04%,
H - 7.45~, N ~ 8.09~.
