Broad-Spectrum Radical Cyclizations Boosted by Polarity Matching. Carbonylative Access to α-Stannylmethylene Lactams from Azaenynes and CO

Abstract

Free-radical mediated stannylcarbonylation of azaenynes provides a general [n + 1]-type annulation approach leading to alpha-stannylmethylene lactams. The cyclization is unusual in its breadth, covering 4-exo, 5-exo, 6-exo, 7-exo, and 8-exo modes.