Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
Z~3~70
The present invention provides a process for preparing N-alkylethyl-
enediamines wherein the alkyl is from C3 to about C6. An alkyl halide wherein
the alkyl is from C3 to about C6 is reacted with ethylenediamine (EDA) at a
temperature of from about -10C. to about 120C. and at a mole ratio of EDA to
said alkyl halide of about 1-20:1, in the presence of about 0-50% by weight of
water, to form a reaction mixture containing N-alkylethylenediamine. The res-
ulting reaction mixture is then neutralized by contact with an aqueous solution
containing about 1 to 2 mol~cular equivalents of an inorganic alkalizing agent
based on the alkyl halide to form a mixture consisting of an inorganic halide,
an aqueous phase, and an organic phase, from which the organic phase is separa-
ted. The organic layer is diluted with about 0.02-100% by weight of a suitable
hydrocarbon solvent selected from the group consisting of n-heptane, isooctane,
cyclohexane, n-hexane, me~hylcyclohexane and _-pentane, and the resulting mix-
ture is azeotropically fractionally distilled to remove all the water and
unreacted EDA therefrom. The resulting reaction mixture is then fractionally
distilled to remove residual hydrocarbon solvent and recover the N-alkylethyl-
enediamine in a purity greater than about 99%.
Preferably, the reaction between the alkyl halide and the EDA is
carried out at about 25-50C in the presence of about 0-30% by weight of water
and at a mole ratio of EDA to alkyl halide of about 2-5:1. The resulting reac-
tion mixture is then contacted with an aqueous caustic soda and the organic
layer is dilut0d with about 0.02-20% by weight of the hydrocarbon solvent
before carrying out the distillation.
The process of the subject invention can be modified by the addi-
tional steps of~ recovering and recycling aqueous EDA from the azeotrope,
~2) recovering and recycling the hydrocarbon solvent, and ~3) contacting the
separated, alkalized aqueous layer with about 10-100% by weight of said hydro-
-- 1 --
`. ~3 ' ~
. :
~2~3~7~
carbon solvent based on the weight of said organic layer, separating the extrac-
ted aqueous layer and diluting the organic layer with the hydrocarbon extract
before proceeding with the azeotropic fractional distillation.
The present invention also provides processes for the removal of
water and/or EDA from the N-alkylethylenediamine by adding a suitable hydrocar-
bon solvent thereto, azeotropically fractionally distilling the water andtor
EDA therefrom, and fractionally distilling to remove residual hydrocarbon sol-
vent and recover anhydrous and/or EDA-free, N-alkylethylenediamine. The
advantages of the process of the present invention over previously available
processes are that (1) the final product has a purity greater than about 99%;
and (2) the process results in high yields and high productivity.
In accordance with the present invention there is also provided an
alternative process for preparing N-alkylethylenediamine of about 99% purity
wherein the alkyl is from C3 to C6 comprising (a) reacting an alkyl halide and
EDA at a mole ratio of EDA to said alkyl halide of about 1-20:1 and a tempera-
ture of about -10C to about 120C under anhydrous conditions to obtain an
alkylation reaction mixture; (b) adding thereto about 0.02-100% by weight,
based on the weight of said alkylation reaction mixture of a suitable hydro-
carbon solvent selected from the group consisting of n-heptanc, isooctane,
cyclohexane, n-hexane, methylcyclohexane and _-pentane; (c) azeotropically
fractionally distilling the mixture of EDA and said hydrocarbon solvent to
essentially remove EDA from the mixture; (d) neutralizing the resulting reac-
tion mixture by contacting it with at least 0.9 molecular equivalent of a
suitable alkalizing agent
~,!,.,_ ~ J
~L28~70
per mole of said alkyl halide to form a slurry of an alkali
halide precipitate; (e) separating said alkali halide from
said slurry and recovering the resulting mother liquor there-
from; (f) washing said separated alkali halide with said hydro-
5 carbon solvent; (g) azeotropically fractionally distilling acombination of said mother liquor from step (e) plus recov-
ered hydrocarbon wash liquor from step (f) to remove essen-
tially all water and residual EDA from the resulting mixture;
and (h) fractionally distilling the resulting reaction mix-
10 ture to remove residual hydrocarbon solvent and recover saidN-alkylethylenediamine.
EDA, either as an anhydrous liquid or containing
water, and an alkyl halide, preferably an alkyl chloride,
are admixed in a suitable reactor vessel while agitating and
15 maintaining the reaction mixture at from about -10C to about
120C. (pref~rably at about 25-50C), over a period of about
5-15 hours (preferably about 7-9 hours), to provide a mole
ratio of EDA to alkyl halide of about 1-20:1 (preferably about
2-5:1) and form a reaction mixture containing about 0-50% by
20 weight of water (preferably about 0-30%). Suitable alkyl
halides include propyl chloride, isopropyl chloride, butyl
chloride, pentyl chloride, l-hexyl chloride, and 3-hexyl
chloride. The total residence time in the reactor vessel de-
pends on the temperature employed, with shorter residence times
25 employed with higher tempera~ures.
The reaction mixture is then vigorously contacted
with an aqueous solution of an alkalizing agent to form a
mixture, consisting of an organic layer, an aqueous layer,
and an alkaline halide. Sufficient alkalizing agent is em-
30 ployed so that the pH of the aqueous layer does not go belowabout 7, preferably not below 8 and an aqueous layer is form-
ed. Suitable alkalizing agents include sodium and potassium
hydroxide, either singly or in mixtures. The preferred al-
~28~70
kalizing a~ent is about 50~ a~ueous sodium hydroxide.
The organic layer is separated from the alkaline hal-
ide and the aqueous layer by making a phase separation, or by
first separating the alkaline halide by filtration or centrifu-
gation, and then making a phase separation. The organic layercontains the N-alkylethylenediamine, unreacted EDA, and higher
alkylation products such as N,N'-dialkylethylenediamine, N,N-
-dialkylethylenediamine, N,N,N'-trialkylethylenediamine, and
N,N,N',N'-tetraalkylethylenediamine. The organic layer is then
diluted with about 0.02-100~ by weight, preferably about 0.02-
-20~ by weight, of a suitable hydrocarbon solvent, based
on the weight of said organic layer.
Preferably, the separated aqueous layer is extracted
with about 10-100% by weight, preferably about 10-20% by weight,
of said suitable hydrocarbon solvent, based on the weight of
said organic layer and the two-phase mlxture is allowed to set-
tle. The extracted aqueous layer is then separated and the
hydrocarbon solvent extract is used to dilute the above- men-
tioned organic layer.
As employed herein, the term "suitable hydrocarbon
solvent" is defined as a hydrocarbon solvent which forms an azeo-
trope with water and/or EDA below the boiling point of the pro-
duct N-alkylethylenediamine from which condensed azeotrope water
and/or EDA may be separated from the hydrocarbon without in-
clusion of substantial amount of the N-alkylethylenediamine.
Suitable hydrocarbon solvents include n-heptane, isooctane,
cyclohexane, n-hexane, methylcyclohexane, n-pentane, and the
li~e, although the preferred hydrocarbon solvent is n-heptane.
The diluted organic layer is then heated to boiling
through a distillation column to azeotropically fractionally
distill off any residual EDA and water. After allowing the
distillate to settle, the lower EDA-water layer may be s~a-
rated and recycled to the alkylation vessel, and the upper
hydrocarbon layer may be recycled to the distillation column
until anhydrous EDA-free N-alkylethylenediamine is obtained,
:
-
: .
llZ~070
- 5
or transferred to a vessel for extraction of the original aqu-
eous layer.
The residual EDA-free reaction mixture, containing
N-alkylethylenediamine, higher alkylated ethylenediamines, and
the hydrocarbon solvent is now fractionally distilled, using a
fractionation column containing sufficient theoretical plates,
to separate said hydrocarbon solvent from the N-alkylethylene-
diamine. For example, using a column containing 15 theoretical
plates and n-heptane as the solvent, the n-heptane distills
off as a forerun boiling at about 98-100C. The forerun of
hydrocarbon solvent so obtained may be recycled to other sta-
ges of the process, such as dilution of the organic layer,
azeotroping EDA and water from the reaction mixture, or ex-
tracting the aqueous layer, as described above.
After removal of the forerun of hydrocarbon solvent,
the distillation is continued to obtain the N-alkylethylene-
diamine (purity greater than 99%) in a yield of greater than
60% based on the alkyl halide charged. The procedure employed
herein may also be used to remove water and/or EDA from the
W-alkylethylenediamine by adding a suitable amount of said
hydrocarbon solvent thereto, azeotropically fractionally dls-
tilling the water or EDA, or both, therefrom and fractionally
distilling the residue to remove excess hydrocarbon solvent
and obtain anhydrous, ~DA-free N-alkylethylenediamine. It is
to be understood that the aforedescribed process may also be
carried out continuously using appropriate vessels, such as
continuous flow reactors, splitter vessels, distillation col-
umns, and the like.
In an alternative process ethylenediamine as an an-
hydrous liquid, is reacted with an alkyl halide as shown below
H
RX + H2N-CH2CH2-NH2 > R-NCH2CH2NH2 + HX
wherein X is a halo atom, such as chloro, bromo, or
iodo, preferably chloro. The reaction is carried out while
agitating the reaction mixture in a suitable reactor vessel
~28~70
at about -10C to about 120C, preferably at about 25-75C, over a period of
about 1-24 hours, preferably about 2-6 hours. The mole ratio of EDA to the
alkyl halide employed is about 1-20 to 1, preferably about 2-5 to l. The total
residence time in the reactor vessel will depend on the temperature employed,
with shorter residence times employed with higher temperatures.
Upon completion of the reaction, the reaction mixture is diluted with
about 0.02-100% by weight, preferably about 0.5-1.0% by weight, of a suitable
hydrocarbon solvent, based on the weight of the reaction mixture. As employed
herein the term "suitable hydrocarbon solvent" has the same meaning as previ-
ously defined. The diluted reaction mixture is then heated to boiling througha distillation column to azeotropically fractionally distill off any residual
EDA. Optionally, the EDA distillate may be recovered and recycled.
Suitable hydrocarbon solvents include _-heptane, isooctane, cyclohex-
ane, n-hexane, methylcyclohexane, n-pentane, and the like, although the pre-
ferred hydrocarbon solvent is n-heptane.
The reaction mixture is then neutralized by contacting it with at
least 0.9 molecular equivalent of a suitable alkalizing agent per mole of
alkyl halide used. As employed herein the term "suitable alkalizing agent" is
defined as sodium or potassium hydroxide, either singly or in mixtures. The
preferred alkalizing agent is 50% aqueous sodium hydroxide.
The resulting alkali halide precipitate is separated from the result-
ing slurry by conventional means, such as filtration or centrifugation, and
washed Wit]l the hydrocarbon solvent described previously, preferably with _-
heptane~
The hydrocarbon solvent wash liquors are collected and combined with
the mother liquor obtained by the separation of the alkali halide precipitate
from the slurry formed by the addition of an alkalizing agent to the reaction
mixture. The combined liquors are azeotropically fractionally
-- 6 --
~128~0
distilled at atmospheric pressure through a packed column,
preferably with recycle of heptane distillate to the column,
until the residual material is essentially free of EDA and
water.
The resulting essentially EDA-free reaction mixture,
containing the product N-alkylethylenediamine, higher alkyl-
ated ethylenediamines, and the hydrocarbon solvent is now
fractionally distilled, using a fractionation column contain-
ing sufficient theoretical plates, to separate said hydrocar-
bon solvent from the product N-alkylethylenediamine. For ex-
ample, using a column containing lS theoretical plates, n-
-he~iane distills off as a forerun boiling at about 98-100C.
The forerun of hydrocarbon solvent so obtained may be recyc-
led to other stages of the process, such as dilution of the
lS reaction mixture, or azeotroping EDA or water from the reac-
tion mixture.
After removal of t.he forerun of hydrocarbon solvent
the reaction mixture is preferably clarified to remove any
insolubles and distillation of the clarified solution is con-
tinued to obtain the N-alkylethylenediamine in a purity great-
er than 99~ and a yield of greater than 60% of theoretical
based on the alkyl halide charged.
It is to be understood that the aforedescribed pro-
cess may also be carried out continuously using appropriate
vessels, such as continuous Elow reactors, separation vessels,
distillation columns, and the like.
I The following examples are provided to illustrate
j the invention. Except as otherwise noted, all parts are by
weight and all ranges are inclusive of both numbers. The
purity of the product i5 expressed as area percent, as deter-
mined by vapor phase chromatography (VPC).
ExamPle 1
This example illustrates the use of anhydrous EDA
Ethyl chloride ~565 grams: 8.76 moles) is added to
anhydrous EDA (1420 grams; 23.63 moles) at 30-40C over a
.
1:~28~7~
- ~8 -
period of 5 hours. The reaction mixture is stirred for 2
hours after the addition is completed and 50% caustic soda
(935 ml; 17.5 moles) is added thereto. The resulting mixture
is stirred for 30 minutes, allowed to settle, and the aqueous
salt slurry is separated and extracted twice with 150 ml of
_-he~tane. The heptane extracts are added to the organic
phase and the combined solution is heated to azeotropically
distill water and EDA therefrom at 88-97C., using a frac-
tionation column and a splitter device to return distilled
heptane to the distillation column and to separate the denser
aqueous EDA phase. In this manner an aqueous EDA phase is
se~arated consisting of 394 grams of water and 896 grams of
EDA (14.91 moles). The EDA-free residue is fractionally dis-
tilled to obtain a heptane forerun (b.p. 98-102C.) contain-
ing 3-4% by weight of NEED, and 484 grams of NEED (b.p. 130-
-131C.) of greater than 99.8% purity by VPC. The yield is
62.7% of theoretical based on ethyl chloride.
Example 2
This example illustrates the use of recovered aqueous EDA
Ethyl chloride (545 grams; 8.45 moles) is added at
30-40C. over a period of S hours to a mixture of 1245 grams
of aqueous EDA recovered fron; Example 1 (containing 14.39
moles of EDA) and anhydrous EDA (555 grams; 9.23 moles). The
reaction mixture is stirred for 2 hours after the addition is
completed and 50% caustic soda (902 ml; 16.9 moles) is added
thereto. The resulting mixture is processed as described in
Example 1 utilizing recovered n-heptane from Example 1 to ex-
tract the separated aqueous salt slurry. Fractional distil-
lation of the EDA-free residual material yields a heptane
forerun containing 3-4~ by weight of NEED, and 483 grams of
NEED ~b.p. 130-131C.) of greater than 99.8~ purity by VPC.
The yield is 65% of theoretical based on ethyl chloride.
Example 3
; This example illustrates the separation of EDA from N-Ethyl-
-ethylenediamine by azeotropic distillation
:; :
,
1~28(~
A mixture of EDA (500 grams) and NEED (500 grams)
is diluted with 200 ml. of n-heptane and heated to azeotrop-
ically fractionally distill (b.p. 87-90C) EDA therefrom,
using a distillation column and a device which returns the
recovered heptane to the distillation apparatus and allows
for tile recovery of the denser EDA phase. The EDA thus re-
covered contains less than 1% NEED by VPC. The EDA-free re-
sidue is then fractionally distilled to recover a heptane
forerun and pure NEED (b.p. 130-131C).
In the manner described above, substituting cyclo-
hexane, n-hexane, or isooctane for the n-heptane, similar re-
sults are obtained.
Example 4
This example illustrates the separation of water from N-Eth-
ylethYlenediamine by azeotropic distillation
To a mixture of 56 grams of NEED and 10 grams of
water is added 50 ml. of n-heptane. The mixture is heated to
boiling and the water is azeotropically fractionated (b.p.
88-98C) therefrom using a distillation column and a split-
ter apparatus which returns the recovered heptane to thedistillation apparatus and allows for the removal of the den~
ser water phase. After removal of the water is complete, the
residue is fractionally distilled to recover a heptane fore-
run and NEED (b.p. 130-131C) containing less than 0.2%
water by VPC.
In the manner descri~ed above, substituting cyclo-
hexane, n-hexane, or isooctane for the n-heptane, similar re-
sults are obtained.
Examples 5 to 10 illustrate the recovery of N-ethylethylene-
diamine wherein the EDA is removed before neutralization
Example 5
Ethyl chloride (62.4 grams; 0.967 mole) is added to8tirred ethylenediamine (146.3 grams; 2.43 moles) over a per-
iod of 1 hour while allowing the temperature to rise to 95C.
Upon completion of the addition of the ethyl chloride, n-
-- 10 --
-heptane (34.2 grams) is added thereto and the resulting mix-
ture is azeotropically distilled using a fractionation column
and a Dean~Stark device to collect the two-phase liquid dis-
tillate consisting of a lower layer of ethylenediamine (85.09
grams) and an upper layer of heptane which is recycled back
to the fractionation column until all of the ethylenediamine
is removed therefrom.
The remaining material is cooled to 80C, neutra-
lized with 50~ aqueous sodium hydroxide (77.36 grams; 0.967
mole) and the resulting precipitate of sodium chloride is
separated by filtration to obtain a filter cake and a two-
-phase liquid filtrate. The filter cake is then washed with
heptane (50 mls) and the washing is added to the original
two-phase filtrate.
The resulting two-phase liquid is then azeotropic-
ally distilled using a fractionation column and a Dean-Stark
device to collect the two-phase distillate consisting of n-
-heptane and water. After all of the water is removed the
residue is fractionally distilled to remove any heptane and
recover N-ethylethylenediar,line (54.5 grams; b.p. 130-131C;
64% of theoretical) in a purity of 99%.
Example 6
The procedure of Example 5 is followed in every
detail up to the point of the final distillation. After all
the water is removed by azeotropic distillation the residual
material is filtered to separate a white precipitate (4.32
grams). The filter cake is then washed with heptane (16
grams) and the washing is combined with the filtrate. The
combined filtrate plus washing is then fractionally distilled
to remove heptane and recover N-ethylethylenediamine (53.7
grams; b.p. 130-131C; 63% of theoretical) in 99% purity.
Example 7
To a glass-lined reactor is charged 848 parts of
ethylenediamine (98%) followed by 331 parts of liquid ethyl
chloride, charged through a dip leg at a rate to maintain the
~28~
11 --
reaction mixture at 45-55~C. The mixture is stirred for 2
hours and 91 parts of heptane are added thereto. The excess
ethylenediamine is azeotropically distilled off through a
packed column with recycle of the heptane distillate to the
top of the column. A total of 492 parts of ethylenediamine
is recovered from the distillate for recycle. The reaction
mixture is neutralized with 402 parts of 50~ caustic soda,
cooled to room temperature, and centrifuged to remove the
sodium chloride by-product. The salt cake is washed with 70
parts of heptane and the wash liquor is combined with the
mother liquor in a glass-lined vessel. Water is azeotropically
distilled off from the combined liquors through a packed
column with recycle of the distilled heptane to the top of the
column. After all of the water is removed the heptane is
fractionally distilled off through the packed column to ob-
tain a residue containing 273 parts of N-ethylethylenediamine.
This residue is reserved for subsequent combination with the
residues of ExampleS 8-10.
Example 8
To a glass-lined reactor is charged 492 parts of
: recovered ethylenediamine from Example 7 and 375 parts of
fresh ethylenediamine (98%). To this mixture is charged 331
parts of ethyl chloride at a rate to maintain the reaction
mixture at 55-65C- The mixture is stirred for 2 hours and
45 parts of recovered heptane from Example 7 are added there-
to. The excess ethylenediamine is azeotropically distilled
off through a packed column with recycle of the heptane dis-
¦ tillate to top of the column. A total of 501 parts of ethyl-
¦ enediamine is recovered from the distillate for recycle. The
1 30 reaction mixture is neutralized with 407 parts of 50% caustic
~oda, cooled to room temperature, and centrifuged to remove
the sodium chloride by-product. The salt calce is washed with
78 parts of heptane and the wash liquor is combined with the
mother liquor in a glass-lined vessel. Water is azeotropical-
ly distilled off from the combined liquors through a packed
..
., . . ~ ,~
112~3~7(~
- 12 -
column with recycle of the distilled heptane to the top of the
column. After all of the water is removed the heptane is
fractionally distilled off through the packed column to obtain
a residue containin~ 288 parts of N-ethylethylenediamine.
This residue is reserved for subsequent combination with the
resid-~es of Examples 7, 9 and 10.
Example 9
To a glass-lined reactor is charged 501 parts of re-
covered ethylenediamine from Example 8 and 396 parts of fresh
ethylenediamine (98%). To this mixture is charged 331 parts
of ethyl chloride at a rate to maintain the reaction mixture
at 65-75C. The mixture is stirred for 2 hours and 28 parts
of recovered heptane from Example 8 are added thereto. The
excess ethylenediamine is azeotropically distilled off through
a packed column with recycle of the heptane distillate to the
top of the column. A total of 504 parts of ethylenediamine
is recovered from the distillate for recycle. The reaction
mixture is neutralized with 409 parts of 50% caustic soda,
cooled to room temperature, and centrifuged to remove the
sodium chloride by-product. The salt cake is washed with 82
parts of heptane and the wash liquor is combined with the
mother liquor in a glass-lined vessel. Water is azeotropical-
ly distilled off from the combined liquors through a packed
column with recycle of the distilled heptane to the top of the
column. After all of the water is removed the heptane is
fractionally distilled off through the packed column to obtain
a residue containing 310 parts of N-ethylethylenediamine. This
residue is reserved for subsequent combination with the resi-
dues of Examples 7, 8 and 10.
Example 10
To a glass-lined reactor is charged 504 parts of re-
covered ethylenediamine from Example 9 and 388 parts of fresh
ethylenediamine (98%). To this mixture is charged 331 parts
of ethyl chloride at a rate to maintain the reaction mixture
35 at 5S-65C. The mixture is stirred for 2 hours and 30 parts
112~3~70
- 13 -
of recovered heptane from Example 9 are added thereto. The ex-
cess ethylenediamine is a~eotropically distilled off through
a packed column with recycle of the heptane distillate to the
top o~ the column. A total of 523 parts of ethylenediamine
5 is recovered from the distillate for recycle. The reaction
mixture is neutralized with 409 parts of 50~ caustic soda,
cooled to room temperature, and centrifuged to remove the sod-
ium chloride by-product. The salt cake is washed with 91
parts of heptane and the wash liquor is combined with the mot-
10 her liquor in a glass-lined vessel. Water is azeotropically
distilled off from the combined liquors through a packed col-
umn Witl recycle of the distilled heptane to the top of the
column. After all of the water is removed the heptane is
fractionally distilled off through the packed column to obtain
15 a residue containing 317 parts of N-ethylethylenediamine which
is combined with the residues of Examples 7, 8 and 9. The
resulting material is fractionally distilled through a packed
column at atmospheric pressure to obtain 1120 parts of N-eth-
ylethylenediamine, b.p. 129-131C. The yield is 61.9% of
20 theoretical based on ethyl chloride.
Examples ll_to 13 illustrate the use of n-proPYl halide, iso-
propyl halide and n-butyl halide, respectively, in the invention
Exam~le 11
n-Propyl chloride (327.1 grams; 4.16 moles) is added
25 to anhydrous EDA (988.9 gram3; 16.48 moles) at 20-24C over
a period of one hour. The reaction mixture is stirred for 4
hours after the addition is completed and 50~ caustic soda
~392 ml; 7.35 moles) and water (206 mls) are added thereto.
The resulting mixture is allowed to settle, and the aqueous
30 salt slurry is separated and extracted twice with 280 ml of
n-heptane. The heptane extracts are added to the organic phase
and the combined mixture is heated to azeotropically distill
water and EDA therefrom at 88-97C, using a splitter device
to return distilled heptane to the distillation vessel and to
35 separate the denser aqueous EDA phase. The EDA-free residue
`` l~Z8~17(~ .
- 14 -
is then fractionally distilled to obtain a heptane forerun
(b.p. 97-100C), and a main fraction of 341.3 grams of N-n-
-propylethylenediamine (b.p. 75-77C at 60 mm) of greater than
99% purity by VPC. The yield is 79.5~ of theoretical based
on n-propyl chloride.
Calculated for CsH14N2 : C, 58.77; H, 13.81; N, 27.42
Found : C, 59.08; H, 13.87; N, 27.60
Example 12
Isopropyl chloride (327 grams; 4.16 moles) is added
to anhydrous EDA (988.9 grams; 16.48 moles) at 70C. After
the addition is completed, the reaction mixture is slowly heat-
ed to 100C, cooled to 25C, and mixed with 50% caustic soda
~391 mls; 7.35 moles) and water (206 mls). The resulting mix-
ture is allowed to settle, and the aqueous salt slurry is
lS separated and extracted twice with 200 mls of n-heptane. The
heptane extracts are added to the organic phase and the com-
bined mixture is heated to azeotropically distill water and
EDA therefrom at 88-97C, using a splitter device to return
distilled heptane to the distillation vessel and to separate
the denser aqueous EDA phase. The EDA-free residue is then
fractionally distilled to obtain a heptane forerun (b.p. 97-
100C), and a main fraction of 305 grams of N-isopropylethyl-
enediamine (b.p. 136-137C) of greater than 99~ purity by
VPC. The yield is 71.1% of theoretical based on isopropyl
chloride.
Calculated for C5H14~2 : C, 58.77; H, 13.81; N, 27.42
Found : C, 59.16; H, 13.89; N, 27.28
Example 13
n-Butyl chloride (385.4 grams; 4.16 moles) is added
to anhydrous EDA ~979.0 grams; 16.29 moles) at 20-24C over
a period of one hour. The reaction mixture is stirred at 22-
27C for 4 hours after the addition is completed and 50% cau-
stic soda (935 ml; 7.35 moles) and water (207 mls) are added
thereto. The resulting mixture is allowed to settle, and the
aqueous salt slurry is separated and extracted twice with 200
'~ ~
mls of n-heptane. The heptane extracts are added ta the organ-
ic phase and the combined mixture is heated to azeotropically
distill water and EDA therefrom at 88-97C, using a splitter
device to return distilled heptane to the distillation vessel
and to separate the denser aqueous EDA phase. The EDA-free
residue is then fractionally distilled to obtain a heptane fore-
run (b.p. 96-100C) and a main fraction of 348 grams of N-n-
-butylethylenediamine (b.p. 74-77C at 20-30 mm) of greater
than 99% purity by VPC. The yield is 71.3% of theoretical
based on n-butyl chloride.
Calculated for C6H16N2 : C, 62.01; H, 13.88; N, 24.11
Found : C, 61.51; H, 13.92; N, 24.13
, I
.j ~
~.
