Russian Journal of Organic Chemistry, Vol. 37, No. 8, 2001, pp. 1177 1178. Translated from Zhurnal Organicheskoi Khimii, Vol. 37, No. 8, 2001,
pp. 1236 1237.
Original Russian Text Copyright
2001 by Shainyan, Grigor,eva.
SHORT
COMMUNICATIONS
Unexpected Transformation of Butyl Vinyl Ether
Treated with HF
B. A. Shainyan and A. A. Grigor,eva
Faworsky Irkutsk Institute of Chemistry, Siberian Division, Russian Academy of Sciences, Irkutsk, 664033 Russia
Received May 10, 2001
Hydrogen halides HX (X = Cl, Br) are known to
add to vinyl ethers readily and nearly quantitatively
in the cold affording -haloethyl ethers ROCHXCH3
[1]. No published data appeared concerning the
reaction between the vinyl ethers and HF. We found
that anhydrous hydrogen fluoride does not add to the
double bond of butyl vinyl ether (I). Passing HF
through ether I at 0 C in the absence of a solvent
resulted in formation of poly(butyl vinyl ether)
[ CH(OBu) CH2 ]n (II) as proved by 1H and
13C NMR data. Yet the treating of butyl vinyl ether
with an ether solution of hydrogen fluoride gave rise
to 1-butanol (III), acetaldehyde dibutyl acetal (IV),
and 1,1,4-tributoxybutane (V). The reaction products
were separated by preparative GLC. Apparently the
1-butanol arose due to ether I hydrolysis by traces of
water. Acetals IV and V originate from reaction of
ether I with 1-butanol and acetal IV respectively [2].
(CH3_CH2), 33.58 (OCH2_CH2), 40.50 (OCH_CH2),
69.40 (OCH2), 75.05 (OCH).
(b) Anhydrous ethyl ether (30 ml) was saturated
with HF at cooling to 5 C by passing HF for 20 min
while stirring. At the same temperature to the solu-
tion obtained was added dropwise at stirring 7.5 ml
of ether I dissolved in 20 ml of anhydrous ethyl ether.
The mixture was stirred for 1 h at room temperature.
The excess HF was removed by NaF addition till pH
7.0, then the solution was filtered, the ethyl ether was
distilled off, and the residue was analyzed by GLC
and separated by fractional distillation in three frac-
tions of bp 92 116 C, 79 110 C (16 mm Hg), 110 C
(15 mm Hg). Individual products III V were isolated
by preparative GLC and identified by 1H and
13C NMR spectra and by comparison of refractive
indices with the published data.
Acetaldehyde dibutyl acetal (IV). n2D0 1.4090
Thus in contrast to HCl and HBr HF does not add
to vinyl ethers but in the cold depending on the con-
ditions either initiates a cationic polymerization or
generates hydrolysis and formation of acetals and
their telomers.
(n2D0
1.4090
[3]).
1H
NMR
spectrum
(C1H3C2H2C3H2C4H2O)2C5HC6H3, , ppm: 0.92 t
(6H, C_H3CH2, J 7.3 Hz), 1.25 d (3H, CH3C_H, J
5.3 Hz), 1.38 m (4H, CH3C_H2), 1.52 m (4H,
CH2C_H2CH2), 3.37 d.t (2H, OCHA, J 6.5, 9.3 Hz),
3.54 d.t (2H, OCHB, J 6.6, 9.3 Hz), 4.62 q
(1H, CH,
J
5.4 Hz). 13C NMR spectrum
(C1H3C2H2C3H2C4H2O)2C5HC6H3, C, ppm: 14.09
(C1), 19.69 (C2), 19.84 (C6), 32.27 (C3), 64.76
(C4), 99.60 (C5).
1,1,3-Tributoxybutane (V). n2D0 1.4300(nD20 1.4255
Reaction of vinyl butyl ether (I) with HF. (a) On
cooling 1.1 g of pure vinyl butyl ether I to 0 C a flow
of anhydrous HF was passed through it for 10 min.
The resinous polymer II obtained was dissolved in
[3]). 1H NMR spectrum
(C1H3C2H2C3H2C4H2O)2-
C5HC6H2C7H
(C8H3)OC9H2C10H2C11H2C12H3,
,
ppm: 0.916 t, 0.921 t, 0.927 t (9H, CH2C_H3, J
7.3 Hz), 1.12 d (3H, CHC_H3, J 6.1 Hz), 1.38 m (6H,
C_H2CH3), 1.52 m (6H, CH2C_H2CH2), 1.63 d.d.d
(1H, CHC_HACH, J 4.4, 7.5, 14.0 Hz), 1.76 d.d.d
(1H, CHC_HBCH, J 4.1, 8.5, 13.9 Hz), 3.20 3.65 m
deuterobenzene and analyzed by means of 1H and 13
C
NMR spectroscopy. 1H NMR spectrum, , ppm: 1.02
(3H), 1.4 1.6 (2H), 1.6 2.3 (4H), 3.4 4.0 (3H).
13C NMR spectrum, C, ppm: 14.91 (CH3), 20.67
1070-4280/01/3708-1177$25.00 2001 MAIK Nauka/Interperiodica