Reaction of perfluorinated vinyl ethers with diethylamine

Full text of DOI:10.1134/S1070363211080305

ISSN 1070-3632, Russian Journal of General Chemistry, 2011, Vol. 81, No. 8, pp. 1741–1742. © Pleiades Publishing, Ltd., 2011.
Original Russian Text © I.G. Maslennikov, K.I. Eremin, 2011, published in Zhurnal Obshchei Khimii, 2011, Vol. 81, No. 8, pp. 1399–1400.
LETTERS
TO THE EDITOR
Reaction of Perfluorinated Vinyl Ethers with Diethylamine
I. G. Maslennikov and K. I. Eremin
St. Petersburg State Institute of Technology, Moskovskii pr. 26, St. Petersburg, 190013 Russia
e-mail: igmasl1947@mail.ru
Received April 12, 2011
DOI: 10.1134/S1070363211080305
It is known that perfluorovinyl ethers react with
secondary amines to give the corresponding addition
products [1]. We have found that trifluoromethyl and
heptafluoropropyl trifluorovinyl ethers Ia and Ib react
with diethylamine to give analogous addition products
IIa and IIb.
N,N-Diethyl-1,1,2-trifluoro-2-heptafluoropropoxy-
ethanamine (IIa) was obtained from 10.5 g of diethyl-
amine and 37.7 g of 1,1,2-trifluoro-2-heptafluoropro-
poxyethene (Ib) under stirring at 20–25°C. Yield 84%,
bp 55–56°C (25 mm). 1H NMR spectrum, δ, ppm: 5.94
d (1H, CHF, JHF = 54 Hz), 2.93 q (4H, NCH-2, JHH
=
7 Hz), 1.05 t (6H, CH2CH3, JHH = 7 Hz). 19F NMR
spectrum, δF, ppm: –81.7 s (3F, CF3), –84.9 d and
–87.5 d (1F each, OCF2, JFF = 153 Hz), –87.8 d and
–90.7 d (1F each, NCF2, JFF = 206 Hz), –130.0 s (2F,
CF3CF2), –140.5 d (1F, CHF, JFH = 57 Hz).
RFOCF=CF2 + HNEt2 → RFOCFHCF2NEt2,
Ia, Ib
IIa, IIb
RF = C3F7 (a), CF3 (b).
In the 19F NMR spectra of N,N-diethyl-1,1,2-tri-
fluoro-2-(perfluoroalkoxy)ethanamines IIa and IIb
thus obtained signals from fluorine atoms in the
difluoromethylene group appeared as an AB spin
system, in keeping with the data of [1]. Amines IIa and
IIb turned out to be relatively unstable, and they
became yellowish even on storage in a sealed ampule.
Treatment of amines IIa and IIb with water in the
presence of triethylamine afforded the corresponding
N,N-diethyl-2-fluoro-2-(perfluoroalkoxy)acetamides
IIIa and IIIb.
N,N-Diethyl-1,1,2-trifluoro-2-trifluoromethoxy-
ethanamine (IIb) was synthesized in a similar way
from diethylamine and 1,1,2-trifluoro-2-trifluorometh-
1
oxyethene (Ia). Yield 72%, bp 48–50°C (50 mm). H
NMR spectrum, δ, ppm: 5.79 d (1H, CHF, JHF = 55 Hz),
2.92 q (4H, NCH2, JHH = 7 Hz), 1.05 t (6H, CH2CH3,
J
HH = 7 Hz). 19F NMR spectrum, δF, ppm: –59.9 s (3F,
CF3), –87.8 d and –90.8 d (1F each, CF2, JFF = 205 Hz),
–141.5 d (1F, CHF, JFH = 57 Hz).
N,N-Diethyl-2-fluoro-2-heptafluoropropoxyacet-
amide (IIIa) was synthesized by treatment of amine
RFOCFHCF2NEt2 + H2O + 2 NEt3
IIa, IIb
1
IIa with water in the presence of triethylamine. H
NMR spectrum, δ, ppm: 6.20 d (1H, CHF, JHF = 55 Hz),
3.29 q (4H, NCH2, JHH = 7 Hz), 1.10 t (6H, CH2CH3,
J
CF3), –84.9 d and –87.2 d (2F, OCF2, JFF = 147 Hz),
–129.7 s (2F, CF2CF3), –129.1 d (1F, CHF, JFH = 50 Hz).
→ RFOCFHC(O)NEt2 + 2 HF·NEt3.
IIIa, IIIb
HH = 7 Hz). 19F NMR spectrum, δF, ppm: –81.3 s (3F,
Amine IIb reacted with aniline to produce N,N-
diethyl-2-fluoro-2-trifluoromethoxy-1-(phenylimino)-
ethanamine (IVb).
N,N-Diethyl-2-fluoro-2-trifluoromethoxyacet-
amide (IIIb) was synthesized in a similar way from
amine IIb. H NMR spectrum, δ, ppm: 5.98 d (1H,
RFOCFHCF2NEt2 + С6H5NH2 + 2 NEt3
IIb
1
→ RFOCFHC(=NC6H5)NEt2 + 2 HF·NEt3.
CHF, JHF = 57 Hz), 3.14 q (4H, NCH2, JHH = 7 Hz),
IVb
19
0.92 t (6H, CH2CH3, JHH = 7 Hz). F NMR spectrum,
1
The products structure was confirmed by their H
δF, ppm: –59.3 s (3F, CF3), –131.1 d (1F, CHF, JFH =
57 Hz).
and 19F NMR spectra.
1741

1742
MASLENNIKOV, EREMIN
CHF, JHF = 52 Hz), 3.36 q (4H, NCH2, JHH = 7 Hz),
N,N-Diethyl-2-fluoro-2-trifluoromethoxy-1-phenyl-
19
iminoethanamine (IVb). Amine IIa, 8.6 g, was added
to a solution of 3.3 g of aniline and 7.7 g of
triethylamine in 10 ml of petroleum ether. The mixture
was stirred for 3 h at 40–50°C and cooled to room
temperature, the precipitate was filtered off, and the
filtrate was subjected to vacuum distillation. Yield 9.0 g
1.10 t (6H, CH2CH3, JHH = 7 Hz). F NMR spectrum,
δF, ppm: –58.6 s (3F, CF3), –128.4 d (1F, CHF, JFH
=
57 Hz). Found, %: C 53.08; H 5.28; N 10.23.
C13H16F4N2O. Calculated, %: C 53.42; H 5.57; N 9.58.
REFERENCE
1
(61.6%), bp 108–109°C (12 mm). H NMR spectrum,
1. Furin, G.G., Salmanov, I.A., and Kiriyanko, V.G., Zh.
Prikl. Khim., 1999, vol. 72, no. 8, p. 1345.
δ, ppm: 7.13 t (2H, o-H, JHH = 8 Hz), 6.87 t (1H, p-H,
JHH = 8 Hz), 6.60 d (2H, m-H, JHH = 8 Hz), 6.28 d (1H,
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 81 No. 8 2011