Silylmethyl-Substituted Aziridine and Azetidine as Masked 1,3- and 1,4-Dipoles for Formal [3 + 2] and [4 + 2] Cycloaddition Reactions

摘要: 2-tert-Butyldiphenylsilylmethyl-substituted aziridine and the corresponding azetidine reacted efficiently with nitriles carbonyl substrates to generate imidazoline, oxazolidine, tetrahydropyrimidine products. The rearranged pyrrolidine skeleton involving migration of silicon under BF3·Et2O conditions. tert-butyldiphenylsilylmethyl function, latent CH2OH group, controlled not only regioselectivity cleavage but also relative stereochemistry substituents in products derived from substituted aziridine.