Photochemical deazetation of 2,3-diazabicyclo[2.2.2]oct-2-ene; unexpected inversion of stereochemistry
Abstract
Irradiation of cis-anti-[5,6-2H2]-2,3-diazabicyclo[2.2.2]oct-2-ene leads to bicyclo[2.2.0]hexane in which the deuterium is predominantly exo, i.e., with inversion of configuration, and hexa-1,6-diene in which the 1,6-positions show equal amounts of cis and trans deuterium; the inversion is explained in terms of one-bond cleavage and conformational changes in a diazenyl biradical.