RYABUKHIN, VASIL’EV
1850
ylphenyl)-3-phenylprop-2-ynamide (Ib) gives rise to
94% of quinolinone IIb. When the reaction time was
shortened to 75 h, the yields of quinolinones IIb and
IIc from amides Ib and Ic were 40 and 36%, respec-
tively, and the substrate conversion was not complete.
In these cases, no vinyl trifluoromethanesulfonates
analogous to compound Z-III were detected in the
reaction mixtures.
4-Phenylquinolin-2(1H)-one (IIa). a. The reaction
of 50 mg (0.23 mmol) of amide Ia in 2 ml of CF3SO3H
at 20°C in 30 days gave 44 mg (88%) of IIa.
b. Quinolinone IIa was obtained together with com-
pound Z-III from 50 mg (0.23 mmol) of amide Ia and
2 ml of CF3SO3H at 50°C in 2 h. Yield 26 mg (52%),
mp 256–258°C; published data [4]: mp 259–261°C.
IR spectrum (KBr), ν, cm–1: 3320 (NH), 1661 (C=O).
1H NMR spectrum (400 MHz), δ, ppm: 6.68 s (1H,
=CH), 7.17 t (1H, Harom, J = 7.6 Hz), 7.43–7.57 m (8H,
Harom), 12.07 s (1H, NH). 13C NMR spectrum, δC, ppm:
116.73 d.d (J = 161, 7 Hz), 119.59 m (J = 4 Hz),
120.75 d (J = 166 Hz), 122.51 d.d (J = 161, 7 Hz),
126.69 d.d (J = 160, 7 Hz), 128.59 d.d (J = 160, 7 Hz),
128.77 d.m (J = 160, 7 Hz), 128.84 d.m (J = 160,
7 Hz), 130.66 d.d (J = 161, 8 Hz), 137.17 m (J =
5 Hz), 138.98 t (J = 8 Hz), 153.44 s, 164.28 s. Mass
spectrum, m/z (Irel, %): 221 (100) [M]+, 193 (26), 165
(35), 139 (7). Calculated: M 221.08.
N-Aryl-3-phenylprop-2-ynamides Ia–Ic were syn-
thesized by reactions of the corresponding anilines
with 3-phenylprop-2-ynoyl chloride at a molar ratio of
2:1 in benzene at 50°C (30 min).
N,3-Diphenylprop-2-ynamide (Ia). Yield 54%,
mp 124–126°C; published data [11]: mp 128°C. IR
spectrum (KBr), ν, cm–1: 3261 (NH), 2211 (C≡C),
1
1643 (C=O). H NMR spectrum (400 MHz), δ, ppm:
7.14 t (1H, Harom, J = 7.8 Hz), 7.34 t (2H, Harom, J =
8.0 Hz), 7.35 t (2H, Harom, J = 7.8 Hz), 7.41 t (1H,
H
arom, J = 8.0 Hz), 7.54 d (2H, Harom, J = 7.8 Hz),
7.59 d (2H, Harom, J = 8.0 Hz), 7.91 s (1H, NH).
7-Methyl-4-phenylquinolin-2(1H)-one (IIb).
a. The reaction of 50 mg (0.21 mmol) of amide Ib in
2 ml of CF3SO3H at 20°C in 30 days gave 47 mg
(94%) of IIb.
N-(3-Methylphenyl)-3-phenylprop-2-ynamide
(Ib). Yield 82%, mp 81–83°C. IR spectrum (KBr), ν,
1
cm–1: 3260 (NH), 2211 (C≡C), 1637 (C=O). H NMR
spectrum (400 MHz), δ, ppm: 2.34 s (3H, Me), 6.96 d
(1H, Harom, J = 7.6 Hz), 7.23 t (1H, Harom, J = 7.6 Hz),
7.34–7.43 m (5H, Harom), 7.55 d (2H, Harom, J = 7.6 Hz),
7.78 s (1H, NH). Found, %: C 81.76; H 5.60; N 6.00.
C16H13NO. Calculated, %: C 81.68; H 5.57; N 5.95.
b. Quinolinone IIb was obtained from 200 mg
(0.84 mmol) of amide Ib in 4 ml of CF3SO3H at 20°C
in 75 h. Yield 80 mg (40%), mp 260–263°C. IR spec-
trum (KBr), ν, cm–1: 3300 (NH), 1658 (C=O). 1H NMR
spectrum (400 MHz), δ, ppm: 2.46 s (3H, Me), 6.65 s
(1H, =CH), 6.98 d (1H, Harom, J = 8.8 Hz), 7.33 s (1H,
Harom), 7.43–7.50 m (6H, Harom), 12.69 s (1H, NH).
Mass spectrum, m/z (Irel, %): 235 (100) [M]+, 234 (28),
206 (15), 178 (7), 165 (8), 152 (14), 77 (12). Found,
%: C 81.72; H 5.62; N 5.97. C16H13NO. Calculated, %:
C 81.68; H 5.57; N 5.95. M 235.10.
N-(4-Methylphenyl)-3-phenylprop-2-ynamide
(Ic). Yield 58%, mp 143–145°C. IR spectrum (CHCl3),
ν, cm–1: 3400 (NH), 2200 (C≡C), 1650 (C=O). 1H NMR
spectrum (400 MHz), δ, ppm: 2.32 s (3H, Me), 7.13 d
(2H, Harom, J = 8.8 Hz), 7.34 t (2H, Harom, J = 7.4 Hz),
7.41 t (1H, Harom, J = 7.4 Hz), 7.47 d (2H, Harom, J =
8.8 Hz), 7.54 t (2H, Harom, J = 7.4 Hz), 7.87 s (1H,
NH). Found, %: C 81.63; H 5.59; N 6.02. C16H13NO.
Calculated, %: C 81.68; H 5.57; N 5.95.
6-Methyl-4-phenylquinolin-2-2(1H)-one (IIc)
was obtained from 50 mg (0.21 mmol) of amide Ic in
2 ml of CF3SO3H at 20°C in 75 h. Yield 18 mg (36%),
mp 243–245°C. IR spectrum (CHCl3), ν, cm–1: 3400
4-Phenylquinolin-2(1H)-ones IIa–IIc (general
procedure). A solution of 0.21–0.84 mmol of amide
Ia–Ic in 2–4 ml of trifluoromethanesulfonic acid was
stirred at 20°C for 75 h or 30 days or at 50°C for 2 h.
The mixture was poured into ~30 ml of ice water and
extracted with chloroform (3×30 ml). The extracts
were combined, washed with water, a saturated aque-
ous solution of NaHCO3, and water again, and dried
over Na2SO4, the solvent was distilled off under re-
duced pressure (water-jet pump), and the residue was
recrystallized from ethanol or subjected to chroma-
tographic separation on silica gel using hexane–ethyl
acetate as eluent.
1
(NH), 1670 (C=O). H NMR spectrum (500 MHz), δ,
ppm: 2.32 s (3H, Me), 6.65 s (1H, =CH), 7.30 s (1H,
Harom), 7.33–7.36 m (2H, Harom), 7.45–7.52 m (5H,
H
arom), 11.88 s (1H, NH). Mass spectrum, m/z (Irel, %):
235 (100) [M]+, 234 (16), 152 (11), 77 (20). Found, %:
C 81.59; H 5.53; N 5.88. C16H13NO. Calculated, %:
C 81.68; H 5.57; N 5.95. M 235.10.
(Z)-N,3-Diphenyl-3-(trifluoromethylsulfonyloxy)-
prop-2-enamide (III) was obtained (together with
compound IIa) from 50 mg (0.23 mmol) of amide Ia
in 2 ml of CF3SO3H at 50°C in 2 h. Yield 25 mg
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 44 No. 12 2008