Unexpected transformations of alkyldiallylamines in the KOH-DMSO system

Article abstract of DOI:10.1023/B:RUGC.0000016025.63629.20

Triallylamine in the KOH-DMSO system readily isomerizes into tri(1-propenyl)amine. Alkyldiallylamines in the same system give 1-ethyl-3-methylcyclohexane along with alkyldi(1-propenyl)amine. The effect of quantity of base and reaction temperature on product ratio was studied. A route of 1-ethyl-3-methyl-cyclohexane formation was proposed.

Full text of DOI:10.1023/B:RUGC.0000016025.63629.20

Russian Journal of General Chemistry, Vol. 73, No. 10, 2003, pp. 1576 1577. Translated from Zhurnal Obshchei Khimii, Vol. 73, No. 10, 2003,
pp. 1669 1670.
Original Russian Text Copyright
2003 by Musorin.
Unexpected Transformations of Alkyldiallylamines
in the KOH DMSO System
G. K. Musorin
Favorskii Irkutsk Institute of Chemistry, Siberian Division, Russian Academy of Sciences, Irkutsk, Russia
Received February 27, 2002
Abstract Triallylamine in the KOH DMSO system readily isomerizes into tri(1-propenyl)amine. Alkyldi-
allylamines in the same system give 1-ethyl-3-methylcyclohexane along with alkyldi(1-propenyl)amine. The
effect of quantity of base and reaction temperature on product ratio was studied. A route of 1-ethyl-3-methyl-
cyclohexane formation was proposed.
It is known that directions of transformations of
allylic heteroatomic compounds in strongly basic
media [alkali metal hydroxide polar aprotic solvent
(DMSO)] are determined by the nature of the hetero-
atom [1 3]. Thus, diallyl ether and diallyl sulfide in
the KOH DMSO system readily isomerize into the
corresponding di(1-propenyl) chalcogenides [1],
whereas diallyl selenide and diallyl telluride in the
same system convert into 1,3,5-hexatriene [2, 3].
The IV:V ratio in the reaction mixture depends on
the quantity of base and on the reaction temperature.
Increasing quantity of potassium hydroxide in the re-
action medium (IIIa:KOH = 1:10, 90 C, 6 h] in-
creases the fraction of compound V (IVa:V = 1:2.2].
The same trend is observed as the reaction tempera-
ture is increased. In more rigid conditions (110 C,
6 h), the IVa:V ratio is 1:3. At 65 C, the conversion
of compound IIIa is 84% and IVa:V = 1:1.
We are the first to find that directions of transforma-
tions of diallylamines in the system KOH DMSO
depend on the nature of the substrate. Whereas trial-
lylamine (I) in the KOH DMSO system (90 C, 6 h)
selectively isomerizes into tri(1-propenyl)amine (II)
in yields of up to 88%, alkyldiallylamines IIIa and
IIIb, along with the isomerization into alkyl(1-pro-
penyl)amines IVa and IVb, can also convert into
1-ethyl-3-methylcyclohexane (V). The IVa:V ratio in
the reaction mixture [90 C, 6 h; IIIa:KOH = 1:4] is
1:1.5. The total yield of compounds IV and V is 66%.
In view of the ability of the KOH DMSO system
to induce radical-anion processes [4], as well as the
ability of alkali metal cations to coordinate with un-
saturated compounds which subsequently convert into
cyclic structures [5], we can propose the following
route of formation of compound V.
e
III
+
N
N
VII
Alk
Alk
R = CH2CH=CH2
N
IV
KOH DMSO
II
N
R = Alk
R
V
I, IIIa, IIIb
N
R
IVa, IVb
Apparently, compound I, containing three acceptor
allyl groups, can hold the unpaired electron in the
radical anion and thus discourages the leaving group
from cleaving with this electron. Substitution of one
allyl group in compound I by an alkyl group makes
the unpaired electron more mobile, produces its
+
V
R = CH2CH=CH2 (I), Et (IIIa), i-Pr (IIIb).
1070-3632/03/7310-1576$25.00 2003 MAIK Nauka/Interperiodica

UNEXPECTED TRANSFORMATIONS OF ALKYLDIALLYLAMINES
1577
Table 1. Reactions of amines I and III with the system KOH DMSOa
Initial reagents
RN(CH2CH=CH2)2
Fractions of the reaction
products in the mixture, %
Total
yield, %
KOH
t,
C
II
IV
V
R
g
mol
g
mol
CH2=CHCH2
CH3CH2
CH3CH2
CH3CH2
CH3CH2
2.7
6.3
2.3
1.6
1.6
1.7
0.02
0.05
0.02
0.01
0.01
0.01
4.5
11.2
11.2
5.6
2.2
2.2
0.08
0.2
0.2
0.1
0.04
0.04
90
90
90
110
65
90
100
88
66
68
58
67
63
38.8
30
25.9
50.8
54.3
58.2
65
78.3
49
CH3(CH3)CH2
44.8
a
Reaction time 6 h, DMSO (50 ml).
Table 2. 1H NMR spectrum of compound IVa
A mixture of 6.3 g of compound IIIa, 11.2 g of
KOH, and 50 ml of DMSO was heated at 90 C for
6 h. The reaction mixture was then diluted with water,
treated with ether, the ether extracts were washed with
water, dried with CaCl2, and distilled to isolate
4.3 g of a mixture containing (by GLC data) 38.8%
of compound IV, 58.2% of compound V, and 3% of
unidentified products. The yields of compounds IV
and V were 27% and 39%, respectively. The other ex-
periments were performed in a similar way (Table 1).
Me
CH2
Me C=C N C=C Me
Ha
Ha
Hb
Hb
Isomers,
, ppm
Ha
Hb
Me
Me
CH2 JH H
a
b
1
The H NMR spectrum of compound IVa is given in
Table 2.
cis,cis
4.71 6.45 1.63 1.18 3.30
4.67 6.49 1.63 1.55 3.26
1.35 3.26
8.5
13.4
1H NMR spectrum of compound V: 0.76 2.06 m
(10H, C6H10), 0.88 0.76 m (3H, CH3CH), 0.91
0.89 m (3H, CH3CH2), 1.14 1.38 m (2H, CH2CH3).
trans,trans
cis,trans
cis
4.72 6.51 1.63
8.7
trans
4.67 6.49 1.64
13.4
By GC MS analysis of the reaction mixture we
found compounds IV (m/e 125), V (m/e 126),
and ethyl(1-propenyl)amine (m/e 85).
shifting, and stimulates cleavage of the leaving group
and favors unusual transformations of compounds III
in the system KOH DMSO.
REFERENCES
1. Trofimov, B.A., Amosova, S.V., Musorin, G.K., Ka-
labin, G.A., Nosyreva, V.V., and Alpert, M.L., Sulfur
Lett., 1986, vol. 4, no. 2, p. 67.
We also detected traces of ethyl(1-propenyl)amine
in the reaction mixture. In the presence of base, this
compound probably converts into ethylamide.
2. Musorin, G.K. and Amosova, S.V., Zh. Org. Khim.,
1992, vol. 28, no. 4, p. 681.
EXPERIMENTAL
3. Musorin, G.K., Zh. Org. Khim., 1997, vol. 67, no. 11,
Gas chromatography was performed on a Chrom-5
chromatograph, column 1000 4 mm, packing 10%
SE-30 on Chromaton N-AW-DMCS. The mass spec-
trum was obtained on an LKB-2091 instrument. The
1H NMR spectra were measured on a Bruker DPX-
400 spectrometer (400.13 MHz) internal reference
HMDS, solvent CDCl3.
p. 1931.
4. Musorin, G.K., Zh. Obshch. Khim., 2000, vol. 70,
no. 12, p. 2052.
5. Trofimov, B.A., Geteroatomnye proizvodnye atsetilena
(Heteroatomic Derivatives of Acetylenes), Moscow:
Nauka, 1981.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 73 No. 10 2003