MEL’NICHENKO, VOVK
1-Aryl-1-chloro-2,2,2-trifluoroethyl isocyanates
150
Methyl 2,2,2-trifluoro-1-phenylethylidenecarba-
mate (IIIa). Yield 68%, bp 60–62°C (0.2 mm), nD20
=
IVa–IVd (general procedure). A mixture of 0.01 mol
of carbamate IIIa–IIIf and 2.5 g (0.012 mol) of phos-
phorus pentachloride in 5 ml of phosphoryl chloride
was heated for 4 h under reflux. The mixture was
cooled, and a stream of dry sulfur dioxide was passed
through the mixture until it no longer warmed up.
Phosphoryl chloride was distilled off, and the residue
was purified by vacuum distillation.
1.4775; published data [7]: bp 105–107°C (12 mm),
nD20 = 1.4785.
Methyl 2,2,2-trifluoro-1-(4-fluorophenyl)ethyli-
denecarbamate (IIIb). Yield 73%, bp 63–64°C
(0.035 mm), nD20 = 1.4636. IR spectrum, ν, cm–1: 1760
(C=O), 1700 (C=N). 1H NMR spectrum, δ, ppm: 3.78 s
(3H, CH3), 7.19–7.24 m (2H, Harom), 7.70–7.75 m (2H,
H
arom). 19F NMR spectrum, δF, ppm: –70.69 (CF3),
–105.84 (FC6H4). Found, %: F 30.74; N 5.88.
C10H7F4NO2. Calculated, %: F 30.50; N 5.62.
1-Chloro-2,2,2-trifluoro-1-(4-fluorophenyl)ethyl
isocyanate (IVb). Yield 79% (from IIIc), 75% (from
IIId), bp 72°C (10 mm), nD20 = 1.4560. IR spectrum:
1
ν 2260 cm–1 (N=C=O). H NMR spectrum, δ, ppm:
Ethyl 2,2,2-trifluoro-1-phenylethylidenecarba-
mate (IIIc). Yield 68% , bp 89–92°C (0.09 mm), nD20 =
1.4675. IR spectrum, ν, cm–1: 1765 (C=O), 1695 (C=N).
1H NMR spectrum, δ, ppm: 1.22 t (3H, CH3), 4.25 q
(2H, CH2), 7.47–7.63 m (5H, Harom). 19F NMR spec-
trum: δF –70.44 ppm (CF3). Found, %: F 22.95; N 5.83.
C11H10F3NO2. Calculated, %: F 23.24; N 5.71.
7.13–7.18 m (2H, Harom), 7.69–7.74 m (2H, Harom).
19F NMR spectrum, δF, ppm: –81.43 (CF3), –110.85
(FC6H4). Found, %: F 30.17; N 5.72. C9H4F4ClNO.
Calculated, %: F 29.94; N 5.53.
The physical constants of isocyanates IVa, IVc, and
IVd coincided with those reported in [4]. Compound
IVa: yield 86% (from IIIa), 74% (from IIIb). Com-
pound IVc: yield 76%. Compound IVd: yield 65%.
Ethyl 2,2,2-trifluoro-1-(4-fluorophenyl)ethyli-
denecarbamate (IIId). Yield 72%, bp 56–58°C
(0.035 mm), nD20 = 1.4603. IR spectrum, ν, cm–1: 1760
(C=O), 1700 (C=N). 1H NMR spectrum, δ, ppm: 1.26 t
(3H, CH3), 4.26 q (2H, CH2), 7.13–7.17 m (2H, Harom),
7.74–7.19 m (2H, Harom). F NMR spectrum, δF, ppm:
–70.81 (CF3), –106.23 (FC6H4). Found, %: F 28.64;
N 5.13. C11H9F4NO2. Calculated, %: F 28.87; N 5.32.
The IR spectra were recorded on a UR-20 spec-
trometer from solutions in methylene chloride. The
1H and 19F NMR spectra were measured in CDCl3 on
a Varian VXR-300 instrument (299.95 and 75.4 MHz,
respectively) relative to tetramethylsilane (1H) or tri-
chlorofluoromethane (19F).
19
Ethyl 2,2,2-trifluoro-1-(4-methylphenyl)ethyli-
denecarbamate (IIIe). Yield 77%, bp 70–72°C
(0.035 mm), nD20 = 1.4771. IR spectrum, ν, cm–1: 1760
(C=O), 1705 (C=N). 1H NMR spectrum, δ, ppm: 1.25 t
(3H, CH3), 2.35 s (3H, CH3), 4.26 q (2H, CH2), 7.26 d
(2H, Harom), 7.54 d (2H, Harom). 19F NMR spectrum:
δF –69.45 ppm (CF3). Found, %: F 22.22; N 5.56.
C12H12F3NO2. Calculated, %: F 21.99; N 5.40.
REFERENCES
1. Gorbatenko, V.I. and Samarai, L.I., Synthesis, 1980,
no. 2, p. 85.
2. Samarai, L.I., Gorbatenko, V.I., and Vovk, M.V., Ukr.
Khim. Zh., 1989, vol. 55, p. 966.
3. Bol’but, A.V. and Vovk, M.V., Zh. Org. Farm. Khіm.,
2003, vol. 1, p. 26.
Ethyl 2,2,2-trifluoro-1-(4-methoxyphenyl)ethyli-
denecarbamate (IIIf). Yield 71%, bp 95°C
(0.035 mm), nD20 = 1.4985. IR spectrum, ν, cm–1: 1755
(C=O), 1690 (C=N). 1H NMR spectrum, δ, ppm: 1.28 t
(3H, CH3), 3.78 s (3H, CH3O), 4.20 q (2H, CH2),
6.97 d (2H, Harom), 7.62 d (2H, Harom). 19F NMR spec-
trum: δF –70.08 ppm (CF3). Found, %: F 20.90; N 5.31.
C12H12F3NO3. Calculated, %: F 20.71; N 5.09.
4. Fetyukhin, V.N., Koretskii, A.S., Gorbatenko, V.I., and
Samarai, L.I., Zh. Org. Khim., 1977, vol. 13, p. 271.
5. Shokol, V.I., Kozhushko, B.N., and Kirsanov, A.V.,
Zh. Obshch. Khim., 1973, vol. 43, p. 544.
6. Fetyukhin, V.N., Vovk, M.V., and Samarai, L.I., Zh. Org.
Khim., 1981, vol. 17, p. 1420.
7. Vovk, M.V., Dorokhov, V.I., and Samarai, L.I., Zh. Org.
Khim., 1989, vol. 25, p. 754.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 44 No. 1 2008