The Ruppert–Prakash reagent is the most powerful and well-documented reagent for trifluoromethylation. Despite its versatility, no general method exists for its use in a flow system. Here we report the first flow trifluoromethylation of carbonylcompounds and its utility for drug synthesis of efavirenz and HSD-016, including preliminary results of enantioselective variants.
Efavirenz is manufactured worldwide, and its asymmetric synthesis requires a complex organometallic approach, while an organocatalytic approach is far less efficient. The first highly enantioselective approach is disclosed for the synthesis of Efavirenz under nonmetal organocatalysis with up to 93% ee for the Merck intermediate and 91% ee for the Lonsa intermediate using novel alkynyl cinchona catalysts