An Improved Synthesis of Trimethylsilylmethyl Isocyanide and Some of Its Reactions with Nucleophiles

Abstract
Me thy lides derived from formamidines, thioformimidates and imidates (e.g. 1) have recently been revealed as useful 1,3-dipoles for the synthesis of several alkaloids.1–3 Dipoles of this general type are typically generated via the sequential alkylation-fluoride mediated disilylation of the corresponding formamidine, thioformimidate or imidate (e.g. 2). In this note we will disclose our observations on the scope and limitations associated with the formation of these species by the insertion reactions of protic nucleophiles with trimethylsilylmethyl isocyanide (3) and describe an improved synthesis for the latter compound.