Pericyclic reactions. The synthesis and reactions of deuterium labelled cyclohexa-1,4-diene and cyclohexa-1,3-diene

The stereospecific syntheses of trans-3,6-dideuteriocyclohexa-1,4-diene (1) and cis-5,6-dideuteriocyclohexa-1,3-diene (2) are outlined; decomposition of these compounds to benzene and hydrogen shows that only cyclohexa-1,4-diene loses hydrogen stereospecifically; dehydrogenation of (1) and (2) by a variety of reagents is non-stereospecific.