1036
KHACHIKYAN et al.
1H NMR spectrum (DMSO-d6 + CCl4, 1:3),
2,3-dichloro-2-methylpropionic acid and 1 g of tri-
phenylphosphine was refluxed for 12 h in acetonitrile.
The reaction mixture was poured into ether, and the
crystals obtained were filtered off, thoroughly washed
with ether, and dried in a vacuum. Compound I was
,
ppm: 1.4 d (3H, CH3), 2.9 m (1H, CH), 3.30 s (3H,
OCH3), 3.85 m (1H, CH2), 4.20 t (1H, CH2), 7.65
7.75 m (15H, 3C6H5). 31P NMR spectrum, P, ppm:
28.24. Found, %: C 61.9, H 5.1, Br 17.8, C23H24Br
O2P. Calculated, %: C 62.3, H 5.4, Br 18.0.
1
obtained in a yield of 0.56 g (43%), mp 185 C. H
NMR spectrum (DMSO-d6 + CCl4, 1:3), , ppm
(J, Hz): 2.90 m (1H, CH), 4.25 br.d (2H, CH2, J 14.8,
11.1), 5.30 br.t (2H, CH2, J 14.8), 7.60 7.79 m (30H,
6C6H5). Found, %: C 70.2; H 5.12; Cl 10.2. C40H36
Cl2O2P2. Calculated, %: C 70.5; H 5.29; Cl 10.4.
When a solution of 0.65 g of methyl 2,3-dibromo-
2-methylpropionate and 1.31 g of triphenylphosphine
in acetonitrile was refluxed for 12 h and treated as
described above, 0.53 g (88%) of triphenylphosphine
oxide and a 2.5:1 mixture of salts V and IV
(1H and 31P NMR data) in 80% yield were obtained.
Triphenylphosphine was recovered in an amount
of 0.55 g (50%).
Yield of V 0.57 g (53.3%). 1H NMR spectrum
(DMSO-d6 + CCl4, 1:3), , ppm: 1.3 d (3H, CH3),
2.95 m (1H, CH), 3.90 m (1H, CH2), 4.23 t (1H, CH2),
Reaction of methyl 2,3-dichloro-2-methylpro-
pionate with triphenylphosphine. A mixture of
0.86 g of methyl 2,3-dichloro-2-methylpropionate and
2.62 g of triphenylphosphine was refluxed for 12 h in
acetonitrile. The reaction mixture was poured into
ether. The crystals obtained were filtered off, thorough-
ly washed with ether, and dried in a vacuum. A mix-
ture of compounds II and III in 4:1 ratio was ob-
7.70 8.0 m (15H, 3C6H5). 31P NMR spectrum:
P
P
28.80 ppm. Yield of IV 0.22 g (20%). The 1H and 31
NMR data agree with those presented above.
Reaction of 2,3-dibromo-2-methylpropionic acid
with triphenylphosphine. A solution of 0.9 g of 2,3-
dibromo-2-methylpropionic acid and 1.9 g of tri-
phenylphosphine in acetonitrile was left for 15 min at
room temperature. The mixture spontaneously
warmed up, and a precipitate formed. The precipitate
was filtered off, thoroughly washed with acetonitrile,
and dried in a vacuum. Compound VI, 1 g (38.5%)
was obtained, mp 166 168 C. 1H NMR spectrum
(DMSO-d6 + CCl4 1:3), , ppm: 1.30 d (3H, CH3),
2.80 m (1H, CH), 3.85 d (2H, CH2), 7.40 7.79 m
(30H, 6C6H5). Found, %: C 64.1; H 4.5; Br 21.6.
C39H36Br2P2. Calculated, %: C 64.5; H 4.96; Br 22.0.
1
tained; yield 0.5 g. H NMR spectrum of II (DMSO-
d6 + CCl4, 1:3), , ppm: 2.75 m (1H, CH), 3.40 s
(3H, OCH3), 4.30 br.d (2H, CH2), 5.50 br.t (2H, CH2),
1
7.70 7.80 m (30H, 6C6H5). H NMR spectrum of III
(DMSO-d6 + CCl4), , ppm: 2.70 s (3H, OCH3), 5.0 d
(2H, CH2), 6.15 d.d (1H, =CH2), 7.55 7.70 m (15H,
3C6H5).
Triphenylphosphine was recovered in an amount of
2 g (78%).
When a mixture of 0.215 g of methyl 2,3-dichloro-
2-methylpropionate and 0.66 g of triphenylphosphine
was refluxed for 40 h, 0.3 g (33%) of II was obtained,
Triphenylphosphine was recovered in an amount of
0.9 g (47%).
1
mp 143 C. The H NMR data agree with those pre-
sented above. Found, %: C 70.5; H 5.2; Cl 9.9. C41H38
Cl2O2P2. Calculated, %: C 70.8; H 5.47; Cl 10.2.
When a solution of 0.9 g of 2,3-dibromo-2-methyl-
propionic acid and 1.9 g of triphenylphosphine was
refluxed in acetonitrile, 1.2 g (46%) of VI was
obtained.
Triphenylphosphine was recovered in an amount of
0.38 g (56%).
Reaction of methyl 2,3-dibromo-2-methylpro-
pionate with triphenylphosphine. A solution of
1.3 g of methyl 2,3-dibromo-2-methylpropionate and
2.62 g of triphenylphosphine in acetonitrile was left at
room temperature for 15 min. Heat evolution was
observed. The reaction mixture was poured into water.
The crystals obtained were filtered off and thoroughly
washed with water. Triphenylphosphine oxide, 1.2 g
(86%), was obtained, mp 154 C. The aqueous filtrate
was extracted with chloroform, and the organic solu-
tion was treated with ether to precipitate crystals of
IV. Yield 0.7 g (32%), mp 144 145 C.
Triphenylphosphine was recovered in an amount of
0.8 g (42%).
REFERENCES
1. Khachikyan, R.Dzh., Tovmasyan, N.V., and Indzhi-
kyan, M.G., Zh. Obshch. Khim., 2005, vol. 75, no. 12,
p. 1978.
2. Khachikyan, R.Dzh., Tovmasyan, N.V., Panosyan, G.A.,
and Indzhikyan, M.G., Zh. Obshch. Khim., 2006,
vol. 76, no. 10, p. 1617.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 77 No. 6 2007