[2-[(1-Benzotriazol-1-ylmethylsulfanyl)-5-chlorophenyl](4-methylphenyl)methanone (5f). White
powder (DMF–water), 106-107°C (87%). 1H NMR, δ, ppm: 2.41 (3H, s); 5.89 (2H, s); 7.08 (1H, d, J = 8.4 Hz);
13
7.16-7.21 (3H, m,); 7.28-7.36 (4H, m); 7.55 (2H, d, J = 8.1 Hz); 7.99-8.02 (1H, m). C NMR, δ, ppm: 21.8,
52.5, 109.8, 120.0, 124.1, 127.5, 127.7, 128.2, 129.4, 130.2, 130.3, 132.3, 133.6, 135.2, 136.5, 145.1, 145.4,
146.0, 194.7. Found, %: C 64.17; H 4.18; N 10.53. C21H16ClN3OS. Calculated, %: C 64.03; H 4.09; N 10.67.
{2-[1-(1-Benzotriazol-1-yl)ethylsulfanyl]phenyl}(phenyl)methanone (5g). White plates (benzene–
hexane); mp 135-136°C (68%). 1H NMR, δ, ppm: 2.03-2.04 (3H, d, J = 6.9 Hz); 6.46 (1H, q, J = 6.9 Hz); 6.98
(1H, d, J = 7.7 Hz); 7.07-7.11 (1H, m); 7.22-7.27 (4H, m); 7.40 (2H, t, J = 7.5 Hz); 7.49-7.64 (4H, m); 7.95-7.98
13
(1H, m). C NMR, δ, ppm: 20.5, 62.9, 110.7, 119.8, 123.9, 127.0, 128.3, 128.4, 128.5, 129.8, 130.0, 130.3,
131.8, 133.5, 135.3, 136.7, 143.5, 146.1, 196.6. Found, %: C 70.55; H 4.92; N 11.53. C21H17N3OS.
Calculated, %: C 70.17; H 4.77; N 11.69.
{2-[1-(1-Benzotriazol-1-yl)ethylsulfanyl]phenyl}(4-methylphenyl)methanone (5h). Colorless oil
1
(76%). H NMR, δ, ppm: 2.02 (3H, d, J = 6.9 Hz); 2.42 (3H, s); 6.45 (1H, q, J = 6.9 Hz); 6.95 (1H, d,
13
J = 7.5 Hz); 7.03-7.09 (1H, m); 7.18-7.29 (6H, m); 7.47-7.55 (3H, m); 7.94-7.97 (1H, m). C NMR, δ, ppm:
20.6, 21.7, 62.9, 110.7, 119.8, 123.8, 127.0, 128.1, 128.4, 129.2, 129.5, 130.1, 130.2, 131.9, 134.2, 135.4, 144.0,
144.5, 146.0, 196.3. Found, %: C 70.73; H 5.44; N 11.22. C22H19N3OS. Calculated, %: C 70.75; H 5.13;
N 11.25.
{2-[1-(1-Benzotriazol-1-yl)ethylsulfanyl]-5-methylphenyl}(phenyl)methanone (5i). White plates
1
(methylene chloride–hexane); mp 109-111°C (71%). H NMR, δ, ppm: 2.00 (3H, d, J = 6.9 Hz); 2.24 (3H, s);
6.38 (1H, q, J = 6.9 Hz); 6.79 (1H, d, J = 8.1 Hz); 6.88 (1H, d, J = 7.8 Hz); 7.05 (1H, s); 7.23-7.27 (2H, m); 7.40
13
(2H, t, J = 7.5 Hz); 7.49-7.59 (2H, m); 7.64 (2H, d, J = 7.2 Hz); 7.95-7.98 (1H, m). C NMR, δ, ppm: 20.4,
21.0, 63.2, 110.8, 119.8, 123.8, 125.9, 126.9, 128.4, 128.8, 130.0, 131.0, 131.8, 133.4, 135.7, 136.8, 139.1,
144.0, 146.1, 196.8. Found, %: C 70.51; H 5.23; N 11.73. C22H19N3OS. Calculated, %: C 70.75; H 5.13;
N 11.25.
{2-[1-(1-Benzotriazol-1-yl)ethylsulfanyl]-5-methylphenyl}(4-methylphenyl)methanone (5j). White
1
powder (ethyl acetate–hexane); mp 75-76°C (75%). H NMR, δ, ppm: 2.00 (3H, d, J = 7.2 Hz); 2.24 (3H, s);
2.42 (3H, s); 6.37 (1H, q, J = 7.2 Hz,); 6.76 (1H, d, J = 7.8 Hz); 6.85 (1H, d, J = 7.8 Hz); 7.04 (1H, s); 7.18-7.28
13
(4H, m); 7.48-7.51 (1H, m); 7.54 (2H, d, J = 8.1 Hz,); 7.95-7.98 (1H, m). C NMR, δ, 20.4, 21.0, 21.7, 63.2,
110.8, 119.7, 123.7, 125.6, 126.9, 128.6, 129.2, 130.2, 130.8, 131.9, 134.3, 135.8, 139.1, 144.4, 144.4, 146.0,
196.6. Found, %: C 71.38; H 5.56; N 10.90. C23H21N3OS. Calculated, %: C 71.29; H 5.46; N 10.84.
{2-[1-(1-Benzotriazol-1-yl)ethylsulfanyl]-5-chlorophenyl}(4-methylphenyl)methanone
(5k).
1
Colorless plates (methylene chloride); mp 99-101°C (68%). H NMR, δ, ppm: 2.03 (3H, d, J = 7.0 Hz); 2.43
(3H, s,); 6.39 (1H, q, J = 7.0 Hz); 6.81 (1H, d, J = 8.4 Hz); 7.01 (1H, dd, J = 8.4, 2.1 Hz); 7.21-7.29 (5H, m);
7.47-7.50 (1H, m); 7.53 (2H, d, J = 8.1 Hz); 7.97-7.99 (1H, m). 13C NMR, δ, ppm: 20.5, 21.8, 63.0, 110.6, 120.0,
123.9, 127.2, 127.7, 128.0, 129.4, 130.1, 130.2, 131.8, 133.7, 135.2, 136.9, 145.1, 145.7, 146.1, 194.8.
Found, %: C 64.69; H 4.47; N 10.22. C22H18ClN3OS. Calculated, %: C 64.78; H 4.45; N 10.30.
General Procedure for the Preparation of 2-(Benzotriazol-1-yl)-3-substituted-2,3-dihydro-1-
benzothiophen-3-ols of 6. To a stirred solution of o-sulfanylphenyl ketones 5 (1.5 mmol) in THF was added
LDA (2.0 M, 0.85 ml, 1.7 mmol) at -78°C. The reaction mixture was stirred at the same temperature overnight
and then quenched with saturated aqueous NH4Cl and extracted with diethyl ether. The organic layer was dried
over anhydrous Na2SO4 and the solvent was removed in vacuo. The residue was purified by column
chromatography on silica gel.
2-(1-Benzotriazol-1-yl)-3-phenyl-2,3-dihydro-1-benzothiophen-3-ol
(6a).
White
plates;
1
mp 153-156°C (85%). H NMR, δ, ppm: 3.94 (1H, s); 6.76 (1H, s); 7.11 (1H, d, J = 8.4 Hz); 7.26-7.43 (11H,
13
m); 7.89 (1H, d, J = 8.4 Hz). C NMR, δ, ppm: 75.3, 87.9, 111.0, 120.0, 122.5, 124.2, 125.7, 126.1, 126.4,
127.8, 128.5, 128.6, 130.4, 132.8, 137.7, 141.5, 142.7, 146.0. Found, %: C 69.04; H 4.73; N 11.91. C20H15N3OS.
Calculated, %: C 69.54; H 4.38; N 12.16.
161