β-Cyclodextrin-Mediated Enantioselective Photochemical Electrocyclization of 1,3-Dihydro-2H-azepin-2-one.

The photochemical electrocyclization reaction of the title compound in the presence of β-cyclodextrin was examined in different conditions. No enantioselectivity was observed in solution, but solid-state reactions of a 1:1 complex as a suspension or a thin film, followed by reduction, provided (1R,5R)-2-azabicyclo[3.2.0]heptan-3-one in isolated yields up to 79% and with ee values up to 45%.