PREPARATION D'ACRYLAMIDES ET DE METHACRYLAMIDES SUBSTITUES EN N

PROCESS FOR PREPARING N-SUBSTITUTED ACRYLAMIDES AND METHACRYLAMIDES

Abrégé anglais

ABSTRACT
The invention relates to a process for preparing
N-substituted acrylamides and methacrylamides which com-
prises reacting acrylamide or methacrylamide, as the case
may be, with an amine reactant, decomposing the formed
reaction product, and separating out and removing the
formed N-substituted acrylamides or methacrylamides by dis-
tillation means.

Revendications

The embodiment of the invention in which an exclusive property
or privilege is claimed are defined as follows:
1. A process for preparing N-substituted acryl-
amides and methacrylamides of the general formula:
<IMG>
wherein X is selected from the group consisting of hydrogen
and methyl and Y is selected from the group consisting of
NH-R-R1, R2-N-R3, <IMG> and <IMG>, wherein R is selected
Prom the group consisting of linear-chained, branched-
chained, and cyclic alkylene residues with from 1 to about
8 carbon atoms, and phenylene, wherein R1 is selected from
the group consisting of hydrogen, a dialkylamino, an alkoxy
group, wherein the alkyl residue contains from 1 to about 4
carbon atoms, wherein R2, R3, and R4 are selected from the
group consisting of alkyl residues having from 1 to about 4
carbon atoms and wherein R2 and R3 are also capable of
forming a 5 or 6 carbon atom ring, which comprises reacting
acrylamide or methacrylamide with an amine having the
general formula HY, wherein Y has the above-identified
meanings, at a temperature ranging from about 100 to 250°C,
removing formed ammonia and, if present, excess amine or
water or both by distillation; decomposing the formed
N,N'-disubstituted 3-aminopropaneamide at a temperature
ranging from 160 to 350°C and separating the decomposition
products by fractional distillation.
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2. The process according to Claim 1 which
comprises reacting acrylamide or methacrylamide dissolved
in water with the amine.
3. The process according to Claim 1 wherein the
reaction is conducted with crystalline acrylamide or meth-
acrylamide in the presence of effective amidation
catalysts.
4. The process according to Claim 1 wherein the
reaction is conducted at a temperature of about 100 to
190°C.
5. The process according to Claim 1 wherein the
decomposition is conducted at a temperature of about 160
to 270°C.
6. The process according to Claim 1 wherein the
decomposition is conducted in a continuous manner with the
rate at which the disubstituted aminopropaneamide is added
to undergo decomposition equal to the rate at which the
decomposition products are removed.
7. The process according to Claim 1 or 6
wherein the decomposition is conducted under reduced
pressure.
8. The process according to Claim 1 wherein
based on the acrylamide or methacrylamide employed, the
amine reactant is present in a mole ratio of 2:1 to 4:1.
9. The process according to Claim 3 wherein the
catalyst employed is selected from the group consisting of
ammonium chloride and ammonium hydrochlorides of the amine
reactant employed, and acrylic and methacrylic acid salts
of the amine compound employed t and acrylic and
methacrylic acid.
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10. A Process for preparing N-substituted
acrylamides and methaacrylamides of the general formula:
<IMG>
wherein X is selected from the group consisting of hydrogen
and methyl and Y is selected from the group consisting of
NH-R-R1, CH3-N-CH3, wherein R is selected from the group
consisting of linear-chained and branched-chained alkylene
residues with from 2 to about 6 carbon atoms, wherein R1
is selected from the group consisting of the dimethylamino
and the methoxy group, which comprises reacting acrylamide
or methacrylamide with an amine having the general formula
HY, wherein Y has the above-identified meanings, at a tempe-
rature ranging from about 100 to 250°C, removing formed
ammonia and, if present, excess amine or water or both by
distillation; decomposing the formed N,N'-disubstituted
aminopropaneamide at a temperature ranging from 160 to
350°C and separating the decomposition products as they
form by fractional distillation.
11. The process according to Claim 10 which
comprises reacting acrylamide or methacrylamide dissolved
in water with the amine.
12. The process according to Claim 10 wherein
the reaction is conducted with crystalline acrylamide or
methacrylamide in the presence of effective amidation
catalysts.
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13. The process according to Claim 10 wherein
the reaction is conducted at a temperature of about 100 to
190°C
14. The process according to Claim 10 wherein
the decomposition is conducted at a temperature of about
160 to 270°C.
15. The process according to Claim 10 wherein
the decomposition is conducted in a continuous manner with
the rate at which the dissubstituted aminopropaneamide is
added to undergo decomposition equal to the rate at which
the decomposition products are removed.
16. The process assording to Claim 10 or 15
wherein the decomposition is conducted under reduced
pressure.
17. The process according to Claim 10 wherein
based on the acrylamide or methacrylamide employed, the
amine reactant is present in a mole ratio of 2:1 to 4:1.
18. The process according to Claim 10 wherein
the catalyst employed is selected from the group
consisting of ammonium chloride and ammonium hydro-
chlorides of the amine reactant employed, and acrylic and
methacrylic acid salts of the amine compound employed, and
acrylic and methacrylic acid.
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Description

~ 31 7 ~
DESCRIPTION O~ TEIE ART
There are in the prlor art severaL known processes for preparincJ ~1-
substi-tuted acrylamides. A great n~lber of these processes are describecl in
de-tail in European Pa-ten-t Application No. 0 013 416 (published on 7/24/80).
Acrylic esters and acrylamides are often the starting material employed to
prepare these N-substituted acrylamides and methacrylamides in a great number
of these processes. And, to protect the double bond of these acrylic or meth-
acrylic acid derivatives, water, an alcohol or an amine are reacted with the
same, breakin~ the double bond and attaching a protective ~roup to the termi-
nal carbon atom. Af-ter the preparation oE the desirecl amLde, th~3 ~)rotectLve
~roup is then split ofE.
There are, however, problems with empLoying subst:ituted carboxyllc
acid derivatives such as 3-hydroxy or 3-alkoxy-substituted carbo~ylic acid
amides as starting ma-terials in the prepara-tion of N-substituted acrylamides
or methacrylamides as compared to 3-amino carboxylic acid derivatives. Where
they are employed, such as in German ~atent Applications 2 819 735 (published
on 11/8/78), 2 856 383 (published on 7/3/80), 2 911 642 (published on 9/25/80),
2 836 520 (published on 2/28/80) and 2 918 486 (published on 11/13/80) which
are open for public inspection and in European Application 0 013 416, there
are problems in that 3-hydroxy- or 3-alkoxy-substituted carboxylic acid amides
are not easily formed; they are, in fact, formed in a complicated multi-stage
process.
There are also problems when an ester is employed; for example, in
DE OS 2 623 838 (published on 12/15/77), where as a
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starting material a 3-alkoxy propionic ester is employed,
the ester i5 prepared in a separate process apart from the
main reaction sequence~
As disclosed in DE-AS 2 816 516 an additional
- problem is disclosed in employing esters as a startiny
material. From the beginning of the reaction, the ester ~w
,: . .
must be present in a larg~ enough amount so that despite
distillation losses an excess amount of ester is maintained
in the reaction. If when forming the amide not enough
ester is present, the ester must be continuously added to
the reaction with the charying of the amine. In addition,
total reflux cannot be employed because the split-off
alcohol which wou}d form as a result cannot be removed ErQm
the reaction mixturc. ~d finally, the distilled off
ester-alcohol mixture must be worked up.
Not only are there problems with employing these
3-hydroxy-or 3-alkoxy- substituted carboxylic acid deriva-
tives as a starting material in that ~hey are very costly
and time comsuming to prepare, but also there are problems
when the protective group ~that is, 3-hydroxy, or 3-alkoxy
group) of the starting material is split off to re-form the
double bond. Because of these end groups, the pyrolysis
reaction (in which the splitting off occurs) proceeds over
a long period of time and in à discontinuous manner.
Alcohols are split off in the pyrolysis reaction causing
azeotropes to form with whatever amines are present that
have the same boiling point as the alcohols. Separation of ~:~5
the formed product is therefore complicated by these

I ~ 7583n
a~eotropes. ~loreover, a catalyst is re~uired to separate
out the water as disclosed in DE-OS 2 918 486.
In U.S. Patent No. 3,652,671 a Michael adduct of
methacrylic acld and N,N-dialkylalkylerle(liamine ls decom-
posed to form an N-(dialkylaminoalkyl) methacrylamide.
This reaction process also suffers from another disadvan- p~
tage: poor yield. -
Thus, in -the prior art where 3-hydroxy or
3-alkoxy-substituted acrylic or metha~rylic acid esters or
amides, or 3-dialkylaminomethacrylie acid h~ve been
employed as starting materials in a process for the for- -,~
mation of N-substituted acrylamidesl there have been sig-
nlfieant problcms. The long ~nd eompl1eatecl process oP
preparing the starting materials, the long and discontin-
uous pyrolysis process, and the formation of azeotropes
complieating the separation o~ produet, present signifi~
eant drawbacks to their widespread use. It is therefore
the obJect of the present învention to develop a process
for preparing N-substituted acryl- and methacrylamides
in good yields but without the drawbaeks of the prior
art.
SUMMARY OF THE INVE~ITION
-
It has now been unexpectedly and surprisingly
found that N-substituted acryl- or methacrylamides ean be
prepared in high yields in a process in which an aeryl- or
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~ ~ 7sa3~
methacrylamide is transamidified with an amine to protect the double bond as
well and the amine is subsequently split off from the intermediately Eormed
~,N'-disubstituted 3-aminopropaneamide to re-Eorm the double bond. The trans-
amidation reaction can occur in an aqueous solution or nonaqueous environment;
however, when the reaction proceeds in a nonaqueous environment, the reaation
should proceed in the presence of effective catalyst.
According to the present invention there is provided a process for
preparing N-substituted acrylamides and methacrylamides of the general formula:
1 \y
wherein X is selected Erom the group consisting of hydrogen and me~hyl and Y
is selected from the group consisting of NH-R-Rl, R2-N-R3, ~ ~Rq and
0, wherein R is selected Erom the group consisting oE linear-chained,
branched-chained, and cyclic alkylene residues with from 1 to about 8 carbon
atoms, and phenylene,~wherein Rl is selected from the group consisting of hyd-
rogen, a dialkylamino, an alkoxy group, wherein -the alkyl residue contains
from 1 to about 4 carbon atoms, wherein R2, R3 and R4 are selected from the
group consisting of alkyl residues having from 1 to about 4 carbon atoms and
wherein R2 and R3 are also capable of forming a 5 or 6 carbon atom ring, which
comprises reacting acrylamide or methacrylamide with an amine having the gen-
eral formula HY, wherein Y has the above-identified meanings, at a temperature
ranging from about 100 to 250C, re~.oving formed ammonia and, if present, exc-
ess amine or water or both by distillation; decomposing the formed N,~'-disub-
stituted 3-aminopropaneamide at a temperature ranging from 160 to 350C and
separating the decomposition products by fractional distillation.
The acryl- or methacrylamide which is employed as a reactant is
added either in a crystalline or non-c~ystalline form; in the latter case, the
acryl- or methacrylamide is dissolved in an aqueous solution. Thus, aqueous
acryl- or methacrylamide solutions as commercially available and prepared in
known ways from acrylonitrile or methacrylonitrile may be employed.
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I I7S83~
Suitable primary and secondary aliphatic amines which may be reacted
include those which comprise linear, branched, and cyclic carbon structures
having from 1 to 8 carbon atoms. The carbon chain may have attached thereto
further functional groups such as dialkylamino or alkoxy groups.
Representative primary amines include: methylamine, ethylamine, n-
butylamine, cyclohexylamine, 2-ethylhexylamine, and preferably N,N-dimethyl-
propanediamine, N,N-dimethylethanediamine, N,N,2,2-tetramethylpropanediamine,
3-methoxypropylamine. Representative secondary amines include: dimethylamine,
: dibutylamine, morpholine, and N-methylpiperazine~ Representative aromatic
: 10 amines include: anilm e, toluidines, p-methylaniline and p-dimethylaminoani-
~ line~
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,~
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The amine reactant may be added in stoichiometric
amounts or in amounts in excess oP the stoLchiometric amount. ~ ~
A 2 to about 5 fok~ molar amount based Otl the amount ofacryl ~`;`~
or methylacryl nitrile present is preferabLy employed.
A conversion, that is, a transamidation reaction
to form the disubstituted propaneamides can be effected in
a continuous or discontinuous process. The reaction is con-
ducted at a temperature of between about lO0 and 250C,
preferably between about 100 and 190C. Suitable reaction
vessels include: agitator kettles, autoklaves, or heatable
reacti`on tubes. ~. c.~!
It was surprisirl~ly found that the transam1d~tlon s
reaction is notic~bly accelerated by -the presence o~ water.
Thus, it is preferred to employ a 30 percent to 50 percent
aqueous acrylamide solution as commercially available. In
the presence of water in an autoclave reaction at l40C, ,
the transamidation reaction takes place within 2 to 5 hours;
whereas, the reaction of a crystalline acrylamide with a
higher amine takes several days.
It was also unexpectedly and surprisingly found
that when the reaction was run with crystalline acryl or
methacrylamide a noticable acceleration could be achieved
by conducting the reaction in the presence of a catalyst.
The reaction is accelerated by the presence of protons or
ammonium ions. The use o~ commonly employed amidation
catalysts have proved suitable; thus, amine hydrochloride,
ammonium chloride ur acrylic-or methacrylic a~id are all ~,
suitable catalysts. For example, when transamidation is
conducted in the presence of l to 4 percent ammonium compounds
a decrease in reaction time is noticed. That is, the
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reaction is speeded up 20 fold. Since they can be used as
starting materi~ls it is most preferred that acryl or 1,
methacryllc acid be employed as a catalyst; also, as it is
consumed dur~n~ the course of the reaction, no impurities
remain. As catalysts any inorganic or organic protons spen-
ding acid (Broensted acids) can be used such as acetic acid,
formic acid, propionic acid, butyric acid etc., and ortho- ``
phosphoric acid, polyphosphoric acids, sulfuric acid, hydro-
chloric acid etc. The catalys-ts may be used in an amount of
from about 1 to a~out 4 mole'~, b~secl on tlle acrylarnlde an(l
methacrylamLde employed. ~lthough there might bc some sepa- !~"'"
ration and re-us~ problems, other suitabl~ catalysts such as
Lewis acid3 whlch may be empLoyed are homogenous catalysts
such as dialkyl stannic ox~des and in partlcular dibutyl
stannic oxide.
With either method from about 90 to about 92 per-
cent of the acrylamide or methacrylamide is converted into
di-substituted propaneamides. The excess amine remaining is
removed by distillation as is any other element, uch as
water. If water is not present the excess amine need not be
removed by distillation. The distillation operation can be
performed ln a reaction tube in a continuous or discontinuous
fashion. ~-
The reaction product, an N,N'-disubstituted 3-amino-
propaneamide is subsequently decomposed by pyrolysis to leave the
product, an N-substituted ~ -9 ~-, unsaturated carboxylic
acid amide. During the course of the pyrolysis reaction the -~
amine is split off. It is advantageous to effect the pyrolysis
continUuslY and under reduced pressure, with the rate at
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which -the disubstituted propaneamide is added to a heated
flas~ to urlder~o decomposition equal to the r~te at whlch
the decomposition products are removed~ 8y removing the
N-substitutect acryl-or me~hacryl amides as a sidestream
and removing the split off amines in an overhead method,
purities in the order o~ 95 to 98 percent of the N-sub-
stituted acrylamide product are obtained. -;
At lower temperatures it is possible for the
N-substituted acrylamicle -to recombine with a corre~sponding
amine in the pyrolitlc dnd separdting sta~e. To remove
disubstituted propaneamides as a sidestream and to obt~ln
a lar~ely pure amine at the columl) hcadl vlcgorous roflux
has to take place in both column sections. Or as an alter
native, the pyrolysis can he effected ln hdtches arld the
split off products subJecked to ~ractionated distillation.
Although the pyrolysis can be conducted up to '~
temperatures above 350C, the preferred temperature range
is from about 160 to 350C and particularly preferred is
the temperature range from about 160 to 270C.
The split off amine and the propaneamide which is
not pyrolyzed can be readily recycled in the process, as
can be the propaneamide formed by recombination which may ;~.1
occur in the pyrolitic or in the~separating process, or in
both.
In order to inhibit polymerization the reaction
may be conducted in the presence of a polymerization in-
hibitor such as di-ter~iary butyl cresol, ~I,N-diphenyl
phenylenediamine or hydrochinon me-thylether, etc. However,
the addition of a polymerization inhibitor is not compuls-
ory. This is an further advantage of the presentinvention
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E
5 3 7~83(1
since inhibitors or their derivatives formed during the
reaction may affect the subse~uent polymerizatlon of the "~!
product obtained.
The yields of the process oP the present in-
vention are hi~h, up -to about 9S ~ and more.
The following examples more fully illustrate the ~;
invention.
EXAMPLE I
1560 ~rams (12 moles) of N,N,2,2--tetramethylpro-
panediamlne~ 2B4 grams (4 rnoles~ of acrylamide, and 7 ~rams
of acrylic acid were heatcd at 150 to 180 C over a ~our ;,?!nSi
hour period (untll ammonia ~ormation was compl~te). Tha
reaction mlxture containing exces~ amine was added drop-
wise to a heated flask maintained a-t a temperature of
240C at the same rate as the N~N',N',2,2-tetramethyl-3- i.. ~
aminopropyl)-acrylamide was separated out via a column r
under 50 mm pressure and as the split-off amine was sepa-
rated out as a sidestream overhead. The amide fraction
contained about 95 % N(N',N',2,2-tetramethyl-3-aminopro-
pyl)-acrylamide which corresponds to a yield of 92 ~.
EXA~IPLE II
1560 grams (12 moles) of N,N,2,2-tetramethyl-
propanediamine, 284 grams (4 moles) of acrylamide, and
1 gram of ammonium chloride were heated at 150 to 180C
over a 4 hour period until the ammonia formation was com-
plete. The reaction mixture was worked up by a procedure
as described in Example I. The same yields as in ~xample I
were also attained.
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____ __ ~
390 gr.lms (3 mo1cs) of N,N,2,2-tetramet11yl~
propanediamine, 71 gralns ~I mole) of acrylamide, and l qram
of dibutyl stannic oxide were heatec1 at 150 to 170C over
an ei(~ht hour period until tlle ammonia formcltion was com-
plete. The reaction mixture was furt11er processed as des-
cribed in Example I. The amide fraction contained 95 %
N(N',N',2,2-tetramethyl-3-aminopropyl)acrylamide which
corresponds to a yield of 70 ~.
EXA~IPLL LV (CO~IPAI~lSUN)
1560 grams (12 moles~ of N,1~1,2,2-tetramcthylpro~
panetliamlne ar)c1 2~ rams ~4 moles) ot` acrylamido ~/ere
heated at reflux (about 145C)~ Cas chromatogrdprlic obser-
vation of the reaction showed that after a three day period
only about 80 % of the s-tarting material had been converted. ¦
More by-products were protluced using the process than were
produced in Examples 1 and II.
EXAMPLE V
1560 grams (12 moles) of N,1~1,2,2-tetramethylpro-
panediamine and 947 grams of a 30~ aqueous acrylamide
solution were heated in a 5-liter autoklave at 160C under
autogenous pressure for four hours. After removing by ~.~,j;
distillation the formed ammonia, the excess aminc and
water, an oily residue was obtained. The residue was added
dropwise to a heated flask maintained at a temperature of
230C at the same rate as the N~N',N',2,2-tetramethyl-3-
arl~inopropyl) acrylamide was separated out as a sidestream
and as the spli-t-off amine was separated out overhead under
a pressure of 50 mm via a co]umn connected to the flask.
_g _

7 .
3 1 ~3~
N(N',N',2,2-tetramethyl-3-aminopropyl)acrylamide having
a purity of 95 ~ was obtained. lhe total yield lias ~8nu.
EYAMPLE VI
A mixture of 390 parts (3 moles) o~ N,11,2,2-tetra-
methyl-propanediamine anc1 23~.7 parts (l mole) of a 30
aqueous acrylamide solution was conducted trough a tube
reactor heated at 180C, the pressure being 10 bar and the
residence time being -two hours. After Ieaving the reactor,
the formed ammonia, the excess amine, and water ~Yere re-
moved by distillation. The resid~le was dropwise ad(1cc1 to
a flask maintained at a temperature of 240 C at the same
rate as N(N',N',2,2-tetramctl)yl-3-dminQpropyl)acrylamide
was separated out as a sldestredm anc1 the spllt-off amine
was separated 0l1t overhead under a pressure of 50 mm ~ia
a column connected with the flask. NIN',N',2,2-tetramethyl- ~-
3-aminopropyl)acrylamide was obtained in a purity of 98 ~
and a yield of 91 ~. The excess N,N,2,2-tetramethylpropane-
diamine was recycled to the tube reactor after the water
is separated out by azeotrope distillation with toluene.
The split-off amine was directly recycled to the tube
reactor.
EXA~IPLE VII
1224 grams (12 moles) of N,N-dimethylpropane-
diamine, 284 grams (4 moles) of acrylamide, and 7 grams of
acrylic acid were heated at the reflux temperature for a
four hour period. The reaction mixture was added
dropwise to a heated flask maintained ~ -,
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at a temperature of 240C at the same rate as the N(N',N'-
dimethyl-3-aminopropy~l acrylamide was separated out via a
column under ~() nun pressur~ as a sidestream and clS the !~;.,.-.,.
split-off amine was separated out overhead. The amide
fractiont 585 grams, contained 95~ N(N',Nl-dimethyl 3-
aminopropyl)acrylamide which corresponds to a yield of
~9.1%. , "c
EX~MPLE VIII
1224 grams (12 moles) of N,N-dimethylpropane-
diamine, 340 grams of methacrylamide were heated at the
reflux temperature for a nine hour period. ~t the start o~ ~
the reactor, 3 grams of methacrylic acid w~re added to th~ t`
re~ction mixture. Dur:inq ~he course of the reaction, two
more 3 c3ram adclitions of acid were added.
Tlle re~lction m~xture was
added dropwise to a heated flask maintained at a tempera-
ture of 240C at the same rate as the N(N',N'-dimethyl-3-
aminopropyl)methacrylamide was separated out as a
sidestream and as the split-off amine was separated out
overhead. The amide fraction, 608 grams, contained 96%
N(N,N~'-dimethyl-3-aminopropyl)methacrylamide. This
corresponds to a yield of 85.8%.
EX~MPLE IX
1044 grams (12 moles) of n-butylamine, 284 grams
(4 moles) of acrylamide, and i grams of acrylic acid were
heated in an autoclave at 140C for a four hour period.
~.
The excess amine was then distilled off and the residue ~? 5-`'
subjected to a pyrolysis reaction conducted under similar
reaction conditions as those described in the above

I J 7S~3~
examples. Thus, at a pressure of 100 n~l, 1523 grams of
N-n-butylacrylamide were produced: a yield of 90~. ;
~X~W PL~ X ~ k
710 grams (10 moles) of acrylam:ide and 5 grams o~
dimethylamine hydrochloride were filled into a 5-liter
autoclave. 1350 grams (30 moles) of dimethylamine gas was
then charged into the same and subsequently the reaction
mixture was heated at 140C for four hours. After
completion of the reaction, the pressure in the aut:oclave
was reduced to atmospheric pressure. As the reacted
mixture is added dropwise to a heated flask at a temper~ ,"
ature of 200C,th~ dimethylacrylamide therein (85 grams,
which correspond to a yield of 85.9~ is simultaneously
distilled off via a column connected to the flask. The
split-off dimethylamide was condensed in an ace~one/ carbon
dioxide snow cooling trap.
EXAMPLE XI
710 grams (10 moles~ of acrylamide and 3375 grams
of a 40% aqueous dimethylamine solution were heatecl in an
autoclave at 150C for four hours. The excess amine, water,
and formed ammonia were distilled off. The formed residue
was worked up on a similar manner as described in Example
X. 871 grams of N,N-dimethylacrylamide were obtained: a ~'"i
yield of 88%.
EXAMPLE XII
71 grams (1 mole) of acrylamide, 300 grams of N-
methylpiperazine, and 1 gram of acrylic acid were heated at
the reflux temperature. In the following eight hour period,
two additions of acrylic acid of 1 gram each is added to
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the reaction mixture~ Then the excess amine was distilled
off and the solid residue was heated at 300~C. At 100 mm press-
~.,., , .i
ure first the split-off amine WAS distilled off and then
123 grams (79.8~ of N(N'-methylpiperazyl)acrylamide.
EXAMPLE X:[II (COMPARISON)
71 grams (1 mole) of acrylamide and 300 grams of
N-methyl-piperazine were hea~ed in an autoclave at 180C.
The amount of transamidation which took place was measured
by gas chromatography. After a 48 hour per:iod only about
50~ had been converted; therefore, the mixture was not ;,.~.
worked up. t
.
.
~ . i .,