Selective electrophilic di- and monofluorinations for the synthesis of 4-difluoromethyl and 4-fluoromethyl quinazolin(thi)ones by a Selectfluor-triggered multi-component reaction†
Abstract
A simple and efficient domino protocol for the selective synthesis of 4-difluoromethyl and 4-fluoromethyl quinazolin(thi)ones was established from readily available 2-aminoacetophenones and iso(thio)cyanates mediated by Selectfluor. The reaction outcomes are restricted by the reaction environment. Without the use of a base, gem-difluoro-oxylated quinazolin(thi)ones were afforded effectively as a sole product. In contrast, only monofluoro-oxylated analogues were obtained under basic conditions.