ABSTRACT
The photochemical and photophysical properties of small ring compounds such as cyclopropanes and cyclobutanes have been well investigated from the mechanistic and synthetic viewpoints.
The main reaction pathways of conjugated or activated cyclopropanes such as alkenyl-or aryl-substituted cyclopropanes, methylenecyclopropanes, and cyclopropyl ketones include
cis,trans-
photoisomerization, photorearrangement, photoaddition, and photocycloaddition. The photocycloaddition of allenes to carbonyl compounds
and the photoaddition of alcohols to aryl-substituted allenes
have also been reported by several groups. However, little has been reported about the photochemistry of vinylidenecyclopropanes, which have not only allene and cyclopropane units, but also a methylenecyclopropane unit. We have previously reported a convenient method for the synthesis of vinylidenecyclopropanes in good to high yields
.
