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WAENGDONGBUNG et al., Orient. J. Chem., Vol. 32(2), 941-945 (2016)
EXPERIMENTAL
3065, 2962, 1607, 1581, 1464, 1400, 1378, 1117,
736 cm-1; 1H NMR (CDCl3, 400 MHz) d 7.08 (1H, d,
Solventswerepurifiedaccordingtostandard J = 7.6 Hz, 4-H), 6.92 (1H, t, J = 7.6 Hz,6-H), 6.75
methods prior to use, while all other chemicals used (1H, t, J = 7.5 Hz, 5-H), 6.63 (1H, t, J = 8.5 Hz, 7-H),
were commercially available and used as received. 5.22 (1H, t, J = 6.3 Hz, 2-H), 4.13 (1H, brs, NH), 1.88
Melting point was measured on a Sanyo Gallenkamp (2H, quint, J = 7.1 Hz, 1'-H), 1.02 (3H, t, J = 7.4 Hz,
melting point apparatus and compared with that of 2'-H); 13C NMR (CDCl3) d 146.7, 127.2, 125.1, 121.9,
known sample.IR spectra were recorded on a Perkin 120.6, 110.6, 70.2, 31.7, 10.2.
1
Elmer Spectrum One FT-IR Spectrometer. H and
13C NMR spectra were recorded using a VARIAN 2-Isopropyl-2,3-dihydrobenzo[d]thiazole (3d)
MERCURY plus (400 MHz FT NMR).
Yellow liquid;FTIR (neat, n, cm-1) nmax 3465,
3367, 3063, 2962, 2926, 1608, 1508, 1387, 1307,
General procedure for the preparation of 2-alkyl- 1255, 745 cm-1; 1H NMR (CDCl3, 400 MHz) d 7.08
2,3-dihydrobenzo[d]thiazoles
(1H, d, J = 7.5 Hz, 4-H), 6.92 (1H, t, J = 7.6 Hz, 6-H),
To a stirred solution of aliphatic aldehyde 6.73 (1H, t, J = 7.5 Hz, 5-H), 6.61 (1H, d, J = 7.8 Hz,
(7.5 mmol) in dichloromethane (7.5 ml) was added 7-H), 5.16 (1H, d, J = 6.2 Hz, 2-H), 4.20 (1H, brs,
4Å molecular sieves (5.0 g). 2-Aminothiophenol (1) NH), 2.06 – 1.95 (1H, m, 1'-H), 1.03 (6H, d, J = 6.7
(0.63 g, 5.0 mmol) was added dropwise to the mixture Hz, 2' and 3'-H); 13C NMR (CDCl3) d 147.3, 127.1,
and stirred altogether at room temperature for 1.5 125.0, 121.6, 120.2, 109.9, 75.0, 35.8, 18.7,18.3.
- 2 h. After completion of the reaction, the reaction
mixture was filtered to remove the molecular sieves. 2-Hexyl-2,3-dihydrobenzo[d]thiazole (3e)
The solvent was evaporated under reduced pressure.
Yellow liquid;FTIR (neat, n, cm-1) nmax 3371,
The residue was purified by column chromatography 3064, 2924, 2853, 1584, 1516, 1463, 1373, 756, 729
on silica gel with 10% ethyl acetate/hexane as eluant cm-1; 1H NMR (CDCl3, 400 MHz) d 7.06 (1H, d, J =
to give the 2-alkyl-2,3-dihydrobenzo[d]thiazole.
7.6 Hz, 4-H), 6.90 (1H, t, J = 7.6 Hz, 6-H), 6.73 (1H,
t, J = 7.5 Hz, 5-H), 6.64 (1H, d, J = 7.7 Hz,7-H), 5.26
(1H, t, J = 6.5 Hz, 2-H), 4.08 (1H, brs, NH), 1.94 –
2-Propyl-2,3-dihydrobenzo[d]thiazole (3a)
Yellow liquid;FTIR (neat, n, cm-1) nmax 3464, 1.80 (2H, m, 1'-H), 1.48 – 1.18 (8H, m, 2', 3', 4', and
3359, 3064, 2954, 2928, 1607, 1583, 1464, 1307, 5'-H), 0.90 (3H, m, 6'-H); 13C NMR (CDCl3) d 146.6,
1118, 736 cm-1; 1H NMR (CDCl3, 400 MHz) d 7.09 125.8, 125.1, 121.9, 120.8, 110.8, 77.4, 77.1, 76.7,
(1H, d, J = 7.6 Hz, 4-H), 6.97 – 6.89 (1H, m, 6-H), 68.9, 38.6, 31.7, 28.9, 26.1, 22.5, 14.0.
6.76 (1H, dt, J = 7.5 Hz, J = 0.9 Hz, 5-H), 6.64 (1H,
d, J = 7.8 Hz, 7-H), 5.27 (1H, t, J = 6.5 Hz, 2-H), 4.12 2-Benzyl-2,3-dihydrobenzo[d]thiazole (3f)
(1H, brs, NH), 1.86 (2H,dt, J = 10.2 Hz, J = 6.9 Hz,
Yellow liquid;FTIR (neat, n, cm-1) nmax 3361,
1'-H), 1.46 (2H, sex, J = 8.0 Hz, 2'-H), 0.98 (3H, t, 3061, 3027, 2924, 1583, 1465, 1311, 1276, 755, 698
J = 7.4 Hz, 3'-H); 13C NMR (CDCl3) d 146.7, 125.1, cm-1; 1H NMR (CDCl3, 400 MHz) d 7.38 – 7.23 (6H,
122.0, 120.7, 110.8, 68.7, 40.7, 19.4, 13.8.
m, Ar-H), 7.09 (1H, d, J = 7.6 Hz, 4-H), 6.93 (1H, t,
J = 7.6 Hz, 6-H), 6.76 (1H, t, J = 7.5 Hz, 5-H), 6.62
(1H, d, J = 7.7 Hz, 7-H), 5.41 (1H, dd, J = 7.7 Hz, J
2-Methyl-2,3-dihydrobenzo[d]thiazole (3b)
Yellow liquid;FTIR (neat, n, cm-1) nmax 3359, = 6.0 Hz, 2-H), 4.17 (1H, brs, NH), 3.18 (1H, dd, J
2957, 2928, 2869, 1607, 1583, 1464, 1377, 1370, = 13.4, J = 8.1 Hz, 1'-H), 3.09 (1H, dd, J = 13.4 Hz,
736 cm-1; 1H NMR (CDCl3, 400 MHz) d 7.08 (1H, d, J = 5.6 Hz, 1'-H); 13C NMR (CDCl3) d 145.9, 137.0,
J = 7.6 Hz, 4-H), 6.91 (1H, t, J = 7.6 Hz, 6-H), 6.76 129.3, 128.8, 127.0, 125.3, 122.2, 120.6, 110.4, 77.3,
(1H, t, J = 7.5 Hz, 5-H), 6.65 (1H, d, J = 8.3 Hz, 7-H), 77.0, 76.7, 68.9, 45.0.
5.39 (1H, q, J = 6.0 Hz, 2-H), 3.97 (1H, brs, NH), 1.60
(3H, d, J = 12.4, 6.0 Hz, 1'-H); 13CNMR (CDCl3) d 2-Phenylethyl-2,3-dihydrobenzo[d]thiazole (3g)
146.4, 125.2, 122.0, 121.0, 111.1, 63.9, 63.8, 24.4.
Yellow liquid;FTIR (neat, n, cm-1) nmax 3357,
3060, 3025, 2920, 1581, 1466, 1400, 1223, 735, 694
cm-1; 1H NMR (CDCl3, 400 MHz) d 7.34-7.27 (2H, m,
2-Ethyl-2,3-dihydrobenzo[d]thiazole (3c)
Yellow liquid;FTIR (neat, n, cm-1) nmax 3354, 2'' and 6''-H), 7.22 (3H, t, J = 6.8 Hz, 3'', 4'' and 5''-H),