The Chemistry of Pyrrolic Compounds. LVIII. meso-substituted Porphyrins. Further Observations on the Oxidative Cyclization of Bilenes-b

Abstract

The oxidative cyclization of a series of bilenes -b carrying substituted methyl groups at a terminal site (1d-i) has been investigated as an approach to the synthesis of meso-substituted porphyrins . Although in most cases the required porphyrin was formed the yield was generally low and the sequence complicated by the presence of by-products. The usefulness of this procedure as a route to meso -substituted porphyrins is therefore limited although the identification of the by-products has increased our general understanding of the mechanism of the oxidative cyclization.