Hydroxylation by cytochrome P-450 and metalloporphyrin models. Evidence for allylic rearrangement

The allylic hydroxylation of 3,3,6,6-tetradeuteriocyclohexene, methylenecyclohexane, and beta -pinene has been examined with phenobarbital-induced liver microsomal cytochrome P-450 (P-450 sub(LM2)) and with iron porphyrin and chromium porphyrin model systems. Aerobic and peroxide dependent enzymic regimes were investigated with purified P-450 sub(LM2) and with microsomal suspension. Epoixidation and allylic hydroxylation were the primary reactions with all substrates. With 3,3,6,6-tetradeuteriocyclohexene, the major hydroxylation product (60-80%) was the result of hydroxylation at the deuterated allylic site. In all cases, a significant amount (20-40%) of hydroxylation occurred with allylic rearrangement.