Synthesis
To a solution of 2-thio-2,3-dihydrobenzo[d]thiazole-5-carbonitrile (1.0 g, 5.2 mmol) in dichloromethane (10 mL) was slowly added sulfonyl chloride (13.5 g, 100 mmol) at 0 °C. The reaction mixture was then warmed to 25 °C and stirred continuously for 3 hours. Upon completion of the reaction, the mixture was poured into water (200 mL) and the dichloromethane was removed by partial vacuum concentration. The aqueous phase was extracted with ethyl acetate (3 x 90 mL) and the organic phases were combined. The organic phase was washed sequentially with brine (3 x 20 mL), dried over anhydrous sodium sulfate, filtered and concentrated in vacuum. The crude product was purified by silica gel column chromatography with the eluent ratio of petroleum ether:ethyl acetate=15:1 to 10:1 to afford 2-chlorobenzo[d]thiazole-5-carbonitrile (0.4 g, 40% yield) as a yellow solid.1H-NMR (CDCl3, 400MHz): δ 8.26 (d, J=0.8 Hz, 1H), 7.92 (d, J=8.4 Hz, 1H), 7.68 (d, J=8.4 Hz, 1H), 1H), 7.68 (d, J=8.4 Hz, 1H). 1H), 7.68 (dd, J=8.4, 1.6 Hz, 1H).
