Facile synthesis of 2-unsubstituted benzofuran-3-carboxylates using diazo(trimethylsilyl)methylmagnesium bromide

Diazo(trimethylsilyl)methylmagnesium bromide reacted with (o-methoxyphenyl)(oxo)acetates to readily afford 2-unsubstituted benzofuran-3-carboxylates via oxonium ylides formed from the initially generated alkylidenecarbene intermediates.