p-Toluenesulfonic acid → 2,2-Dimethyl-3-[2-trifluoromethyl-2-bromo-2-chloro-1-methylsulfonylethyl]-cyclopropane carboxylic acid

Participants

Reaction Conditions

Reaction Steps

30 mg of p-toluene sulfonic acid were added at 40° C. to a solution of 1 g of the product of Step B and 10 ml of methylene chloride and the reaction mixture was heated for 5 hours at 40° C., then poured on to ice, and decanted. The organic phase was washed with water, dried on sodium sulfate and evaporated to dryness under reduced pressure to obtain 860 mg of [1R-[1α-,3α-(RS*,RS*)]] 2,2-dimethyl-3-[2-trifluoromethyl-2-bromo-2-chloro-1-methylsulfonylethyl]-cyclopropane carboxylic acid melting at 138° C.

Provenance & Evidence