Dimethylformamide → 4-Cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-2,5-dimethyl-3-(dichlorofluoromethylthio)pyrrole

Participants

Reaction Conditions

Reaction Steps

To a solution containing 0.90 g (2.04 mmoles) of the 1-(2,6-dichloro-4-trifluoromethylphenyl)-2,5-dimethyl-3-(dichlorofluoromethylthio)pyrrole prepared above in 8 mL of acetonitrile was added a solution of 0.18 mL (0.29 g, 2.07 mmoles) of chlorosulfonyl isocyanate in 1 mL of acetonitrile dropwise over a 5 minute period. After stirring at 0° C. for 2 hours, a solution of 0.18 mL of dimethylformamide in 1 mL of acetonitrile was added and the reaction mixture was maintained at 0° C. for an additional 1.5 hours. The reaction mixture was then diluted with dichloromethane, washed with water and the organic phase was dried over anhydrous Na2SO4. Removal of the solvent under reduced pressure and column chromatography of the residue on silica gel with 4:1 v/v hexane-EtOAc provided 0.80 g (84%) of 4-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-2,5-dimethyl-3-(dichlorofluoromethylthio)pyrrole (ASE 215) as a pale yellow solid of melting point 138.5° C.

Provenance & Evidence