Diisopropylethylamine → 1,1-Dimethylethyl 4-(5-trifluoromethyl-6-chloro-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)-1-piperidinecarboxylate

Participants

Reaction Conditions

Reaction Steps

1,1-Dimethylethyl 4-[(2-amino-5-chloro-4-trifluoromethylphenyl)amino]-1-piperidinecarboxylate (D62, 2.2 g) was dissolved in 25 ml of dichloromethane at 0° C. and triphosgene (0.6 g) and diisopropylethylamine (1.0 ml) were added and the mixture was stirred at 0° C. for 1 h, then washed with aqueous citric acid, dried over MgSO4, filtered and evaporated The product was chromatographed on silica gel eluting with methanol-dichloromethane mixtures, then crystallised from diethyl ether to yield the subtitle compound, 1.0 g.

Provenance & Evidence