Nonstabilized azomethine ylides (ie those bearing only hydrogens or alkyl groups) can be generated from (2-azaallyl) stannanes and (2-azaallyl) silanes through an intramolecular N- alkylation/demetalation cascade. The resulting ylides undergo [3+ 2] cycloaddition with electron-poor or electron-rich dipolarophiles yielding indolizidines and related 1-aza [m. 3.0] bicycloalkane systems in good yield. An in situ protocol allows for a one-pot, three- ...
