Ammonium Chloride → N-(2-cyanoethyl)-2,2-bisfluoromethyl-6-trifluoromethyl-2H-1-benzopyran-4-carbothioamide

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Reaction Steps

An amount (103 mg) of 4-bromo-2,2-bis(fluoromethyl)-6-trifluoromethyl-2H-1-benzopyran was dissolved in diethyl ether (0.5 ml); to the solution, 1.68 M n-butyllithium (0.18 ml) was added at −10° C. under a nitrogen atmosphere. After stirring the reaction mixture for 10 minutes, copper(I) cyanide (27 mg) and tetrahydrofuran (0.6 ml) were added and the resulting mixture was stirred for 30 minutes at 0° C. Subsequently, a tetrahydrofuran solution (0.3 ml) of 2-cyanoethyl isothiocyanate (34 mg) was added and the mixture was stirred for 4 hours at 0° C. To the reaction mixture, a saturated aqueous solution of ammonium chloride was added, followed by extraction with diethyl ether; the resulting organic layer was washed with 2 N HCl, a saturated aqueous solution of sodium hydrogencarbonate and a saturated aqueous solution of sodium chloride, dried with anhydrous sodium sulfate and concentrated under reduced pressure; the resulting residue was subjected to silica gel column chromatography (eluent; dichloromethane/diethyl ether=10/1) to give the titled compound (8 mg), which was identical to the authentic sample.

Provenance & Evidence