Conversion of MT-sulfone to a trifluoromethyl group by IF5: the application of an MT-sulfone anion as a trifluoromethyl anion equivalent.

An MT-sulfone group was converted to a trifluoromethyl group by treatment with IF(5) after an alkylation reaction. Therefore, an MT-sulfone anion can be used as a trifluoromethyl anion equivalent. The formal asymmetric Michael-addition of a trifluoromethyl anion to crotonaldehyde was also performed.