Studies on the Photochemical Rearrangements of Enantiomerically Pure, Polysubstituted, and Variously Annulated Bicyclo[2.2.2]octenones.

A series of enantiomerically pure bicyclo[2.2.2]octenones, including the lactone-annulated system 26, has been prepared by engaging derivatives of an enzymatically derived and homochiral cis-1,2-dihydrocatechol in inter- or intra-molecular Diels-Alder reactions. Systems such as 26 readily participate in photochemically promoted oxa-di-π-methane rearrangement or 1,3-acyl migration processes to give products such as diquinane 34 or mixtures of cyclobutanone 36 and cyclopropane 38, respectively.