The first example of the use of potassium trinitromethanide as a 1,1-ambiphilic synthon equivalent for the construction of a benzofuran moiety mediated by triethylamine has been developed. The method tolerates a variety of functional groups on the starting quaternary ammonium salt and has been successfully extended to polysubstituted benzofurans. Formation of an o-quinone methide intermediate is postulated as a key to the mechanism of this cascade process.
