THE PHOTOCHEMISTRY OF METYRAPONE

Metyrapone [2-methyl-1,2-di(3-pyridyl)propan-2-one, 1] undergoes effic ient a-cleavage via the n(o) pi triplet. The fate of the resulting ac yl and alkyl radicals has been determined by transient studies as well as through the isolation of the final products, quantum yield measure ments and trapping studies. Processes previously documented for carboc yclic analogues of 1, such as disproportionation and coupling of the a lkyl radicals nd recombination to the starting compound are here accom panied by another major process, viz. coupling with attack of the acyl radical on the pyridine ring, which eventually leads mainly to a poly meric material.