Russian Journal of General Chemistry, Vol. 72, No. 9, 2002, pp. 1488 1489. Translated from Zhurnal Obshchei Khimii, Vol. 72, No. 9, 2002,
pp. 1577 1578.
Original Russian Text Copyright
2002 by M. Gazizov, Pudovik, K. Gazizov, Karimova, Khairullin, Romakhin, Nikitin.
LETTERS
TO THE EDITOR
Reaction of 1-Alkoxy-1-haloalkanes with Orthoformic Esters
M. B. Gazizov, M. A. Pudovik, K. M. Gazizov, R. F. Karimova,
R. A. Khairullin, A. S. Romakhin, and V. V. Nikitin
Kazan State Technological University, Kazan, Tatarstan, Russia
Arbuzov Institute of Organic and Physical Chemistry, Kazan Research Center,
Russian Academy of Sciences, Kazan, Tatarstan, Russia
Received July 23, 2001
We found a previously unknown reaction between
-alkoxy-1-haloalkanes Ia Ie and orthoformic esters
attack by the oxygen lone pair of ortho ethers II on
the electropositive methine carbon atom of com-
pounds I; the subsequent four-membered cyclic elec-
tron transfer leads to compounds III and A. The latter
are unstable and readily decompose into alkyl for-
mates IV and alkyl halides V [1].
1
IIa and IIb, yielding 1,1-dialkoxyalkanes IIIa IIId,
alkyl formates IVa and IVb, and alkyl halides Va and
Vb. On mixing of compounds I and II in a 1:1 ratio,
heat release was observed, weak at Hlg = Cl and
considerable at Hlg = Br. The reaction progress was
1
followed by H NMR spectroscopy.
Dimethoxy(phenyl)metane (IIIb) was obtained
from 7.67 g of compound Ib and 5.72 g of ortho ether
IIa, yield 72%, bp 82 83 C (12 mm) (bp 208 C [2]),
When the reaction products had close boiling
points, they were not isolated individual, and their
20
D
1
n
1.5010. H NMR spectrum (CDCl ), , ppm: 3.2 s
1
3
structures were assessed on the basis of the H NMR
(
6H, OMe), 5.3 s (1H, CH), 7.3 m (5H, Ph).
spectra. Thus, on mixing of compound Ia with tri-
methyl orthoformate, a temperature rise of 4 5 C was
observed. After 6 h, the H NMR spectrum of the re-
action mixture no longer showed signals of the start-
ing compounds ( , ppm: 3.6 s (3H, OMe), 5.33 s (2H,
Diethoxy(phenyl)methane (IIIc) was obtained
1
from 2.05 g of compound Ic and 1.79 g of ortho ether
20
IIb, bp 87 88 C (10 mm), n 1.4842 (bp 217 218 C,
D
15
D
1
n
1.4843 [3]). H NMR spectrum (CDCl ), , ppm:
3
CH ) (compound Ia) and 3.13 s (9H, OMe), 4.75 s
3
3
2
1.13 t (6H, Me, J 7.0 Hz), 3.4 q (4H, OCH , J
HH 2
HH
(
1H, CH) (compound IIa)] and showed the following
7
.0 Hz), 5.42 s (1H, CH), 7.3 m (5H, Ph).
signals: 3.2 s (6H, OMe), 4.31 s (2H, CH ) (com-
2
pound IIIa), 3.6 s (3H, OMe), 7.95 s (1H, CH) (com-
pound IVa), and 2.94 s (3H, Me) (compound Va). In
the other cases, products III were isolated individual
by distillation.
1
,1-Diethoxyethane (IIId). a. Ortho ether IIb,
3
.1 g, was added dropwise with stirring to 3.2 g of
compound Ie. The reaction mixture warmed up from
2 to 29 C. It was stirred at 25 C and distilled to
obtain 0.98 g (63%) of ethyl formate, bp 53 54 C, n
2
2
0
D
1
2
2
20
R CH(OR )Hlg + CH(OR )
3
1.3598 (bp 54.3 C, nD 1.3597 [4]) and 1.5 g (61%) of
2
0
Ia Ie
IIa, IIb
compound IIId, bp 100 101 C, n 1.3810 (bp 102
D
104 C, n2 1.3819 [4]).
0
D
1
2
2
R CH(OR ) + HC(OR ) Hlg,
2
2
IIIa IIId
A
b. Ortho ether IIb, 3.1 g, was added dropwise to
2.27 g of compound Id. The reaction mixture warmed
2
A
HCOOR2 + R Hlg,
IVa, IVb Va, Vb
up by 2 C. After 12 h, it was distilled to obtain 0.96 g
62%) of ethyl formate, bp 53 54 C, n2 1.3596, and
0
(
1
D
1
2
20
I, R = H (a), Ph (b, c), Me (d, e); R = Me (a, b), Et
c e); Hlg = Cl (a d), Br (e). II, R = Me (a), Et (b). III,
.45 g (59%) of compound IIId, bp 100 101 C, nD
2
(
1
.3805.
1
2
1
2
1
R = H, R = Me (a); R = Ph, R = Me (b), Et (c); R =
Me, R2 = Et (d). IV, V, R = Me (a), Et (b).
2
The H NMR spectra were measured on Bruker
1
WP-80 (80 MHz) and Tesla BS-567A (100 MHz)
spectrometers, internal reference TMS.
We suggest that the exchange process begins with
1
070-3632/02/7209-1488$27.00 2002 MAIK Nauka/Interperiodica