Thermal and photochemical decomposition of cycloalkanespirodiazirines

Abstract

The decomposition of the cycloalkanespirodiazirines of ring size 5–8 have been investigated both thermally and photochemically. The thermal reactions are consistent with the formation of the corresponding cycloalkylidenes, which react intramolecularly to give cycloalkenes and bicycloalkanes. Photochemically the diazirine ring breaks down by competitive one- and two-bond rupture to give either the diazocycloalkane or the cycloalkylidene which then react further. In acetic acid the diazo-compounds may be trapped as the corresponding cycloalkyl acetates.