Russian Journal of General Chemistry, Vol. 71, No. 2, 2001, pp. 311 312. Translated from Zhurnal Obshchei Khimii, Vol. 71, No. 2, 2001,
pp. 341 342.
Original Russian Text Copyright
2001 by M. Gazizov, Safina, Khairullin, R. Gazizov.
LETTERS
TO THE EDITOR
New Method of Synthesis of Acetals Containing Phosphorus
in the Alcohol Fragment
M. B. Gazizov, G. G. Safina, R. A. Khairullin, and R. M. Gazizov
Kazan State Technological University, Kazan, Tatarstan, Russia
Received May 4, 2000
We found that the high lability of the dichloro- and
trichloroethanoate groups in dichloro- and trichloro-
acetic acid monoacylals III permits to use the latter
as a third electrophilic reagent in reactions of trialkyl
phosphites I with aldehydes II. Hence, an aldehyde
activated by compound I, that is dipolar ion IV, reacts
with monoacylals III by way of nucleophilic substi-
tution at the methine carbon atom to give quasiphos-
phonium salt V. Dealkylation of the latter under the
action of the dichloro- or trichloroethanoate anions
yields acetals VI which contain a phosphorus atom in
the alcohol fragment. The second reaction product is
alkyl dichloro- or trichloroethanoate VII.
8.03 g of compound IIIa and 1.5 g of ethanal.
Vacuum distillation of the reaction mixture gave
6.57 g (76%) of compound VIb and 2.8 g of
ethyl trichloroethanoate (VIIb), bp 67 C (15 mm,)
n2D0 1.4512. 1H NMR spectrum (CDCl3), , ppm:
1.27 t (CH3, J 7.5 Hz), 425 q (OCH2, J 7.5 Hz).
Published data [2]: bp 62 C (12 mm), n2D0 1.4505.
The reaction between compounds Ib, IIc, and IIIa
was carried out analogously, and its products VIb and
VIIb were isolated pure. With compounds Ia, IIa and
IIIb, the reaction mixture was heated at 50 C for 19 h
until the phosphite odor disappeared completely.
Vacuum distillation of the reaction mixture gave
compound VIa and methyl dichloroethanoate (VIIa),
bp 141 142 C, n2D0 1.4416. 1H NMR spectrum
(CDCl3), , ppm: 3.95 s (CH3O), 6.25 s (CHCl2).
(R1O)3P + R2CHO
II
(R1O)3P+R2CHO ,
I
IV
Published data [2]: mp 142.8 C, n2D0 1.4428.
Dimethyl 1-(ethoxyethyl)phosphonate (VIa). bp
IV + MeCH(OEt)OCOCXCl2
III
66 68 C (0.05 mm), nD20 1.4281. H NMR spectrum
1
XCl2CCOO (R1O)3P+CHR2OCH(OEt)Me
V
(CDCl3), , ppm: 4.75, 4.87 q (1H, CHO2, J 5 Hz),
3.92 m (1H, PCH), 3.67, 3.70 d (6H, POMe, J 11 Hz),
3.5 q (2H, OCH2, J 6.3 Hz), 1.25 d.d (3H, PCHCH3,
J 17.5 and 7.5 Hz), 1.18 d (3H, PCHMe, J 5 Hz),
1.08 t (3H, OCHMe, J 6.3 Hz). 31P NMR spectrum:
P 26 ppm. Found, %: P 13.76. C8H19O5P. Calculated,
%: P 13.69. Published data [2]: bp 73 75 C
(0.06 mm), n2D0 1.4270.
(R1O)2P(O)CHR2OCH(OEt)Me + XCl2CCOOR1.
VI VII
I, R1 = Me (a), Et (b); II, R2 = Me (a), Ph (b); III, X = Cl
(a), H (b); VI, R1 = R2 = Me (a), R1 = Et, R2 = Me (b),
R1 = Et, R2 = Ph (c); VII, R1 = Me, X = H (a), R1 = Et,
R2 = Cl (b).
Diethyl 1-(1-ethoxyethyl)ethylphosphonate (VIb).
Acetals VI were previousy prepared by addition of
1-phosphorylated alcohols to vinyl alkyl ethers [1].
The main restriction of the known method is that a
limited number of such alcohols are available pure.
Our present procedure involves no alcohol synthesis
and thus is free of the above restriction.
bp 76 77 C (0.05 mm), n2D0 1.4251. 31P NMR spect-
rum:
23 mm. Found, %: P 12.23. C10H23O5P. Cal-
P
culated, %: P 12.18. Published data [2]: bp 79 81 C
(0.07 mm), n2D0 1.4264.
Ethyl 1-(1-ethoxyethyl)benzylphosphonate. bp
Reaction of triethyl phosphite (Ib) with 1-ethoxy- 115 116 C (0.05 mm), n2D0 1.4829. 1H NMR spectrum
ethyl trichloroethanoate (IIIa) in the presence of
ethanal (IIa). Phosphite Ib, 5.66 g, was added drop-
wise at a temperature below 18 C to a mixture of
(CDCl3), , ppm: 7.37 m (5H, Ph), 4.70 m (1H,
CHO2), 3.75 4.25 m (5H, POCH2, PCH), 3.45 q (2H,
OCHMe, J 6.7 Hz), 0.75 1.30 m (12H, O2CHMe,
1070-3632/01/7102-0311$25.00 2001 MAIK Nauka/Interperiodica
Gazizov
