Furopyridines. xvi. Photo[2+2]cycloaddition of furo‐[3,2‐c]pyridin‐4(5H)‐one with acrylonitrile

Abstract

The photocycloaddition of furo[3,2‐c]pyridin‐4(5H)‐one (1) and its N‐methyl derivative (1‐Me) to acrylonitrile has been studied. The structures of the photoadducts isolated by column chromatography were determined on the basis of the nuclear magnetic resonance spectroscopy. The cycloaddition of 1 afforded an adduct 2 at the carbonyl oxygen and four possible isomers 3a, 3b, 3c and 3d of cyclobutane‐fused adduct at the 6‐ and 7‐position of 1, and the addition of 1‐Me the N‐methyl derivatives 3a‐Me, 3b‐Me, 3c‐Me and 3d‐Me.