Oxidation of monosubstituted olefins by cytochromes P-450 and heme models: evidence for the formation of aldehydes in addition to epoxides and allylic alcohols.

Aldehydes RCH2CHO are formed in addition to epoxides and allylic alcohols upon oxidation of the monosubstituted olefins RCH=CH2, styrene and 6-phenoxy-hex-1-ene, either by liver microsomal systems in the presence of NADPH and O2 or C6H5IO, or by iron-porphyrin- C6H5IO model systems. These aldehydes do not derive from rearrangement of the corresponding epoxides suggesting that they are formed by an hydrogen migration within an interdiate formed by reaction of the olefin with the active oxygen-iron complex. Heme model studies show that the competition between the three possible routes of oxidation of these olefins is greatly dependent upon the environment of the iron.