Trichloromethanethiol → 5-Chloro-3-p-tolyl-[1,2,4]thiadiazole

関与物質

反応条件

反応手順

A mixture of 4-methylbenzimidamide hydrochloride (1.55 g, 9.08 mmol) and Et3N (4.6 g, 6.33 ml, 45.4 mmol) in DCM (30 mL) was cooled with a NaCl/ice-bath to −10° C. Perchloromethyl mercaptan (1.86 g, 1.09 ml, 9.99 mmol) in DCM (10 mL) was added during 40 min. The resulting yellow suspension was stirred for 20 min at 0° C. and 2 h at RT. Water (40 mL) and aq. 2N NaOH (10 mL) was added. The organic layer was separated and extracted with brine (50 mL). The aqueous layers were extracted with DCM (2×40 mL). The combined organic layers were dried over Na2SO4, filtered off and concentrated in vacuo. The residue was purified by silica chromatography (Flash 50 g Si-cartridge using AcOEt: Heptane 1:19 to 1:9.) to yield 5-chloro-3-p-tolyl-1,2,4-thiadiazole (1.63 g, 7.74 mmol, 85% yield) as light yellow solid.

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