Alkylation and Reduction of Porphyrins andN-Substituted Porphyrins: New Routes to Chlorins and Phlorins

Abstract

On reaction with organolithium compounds, N-substituted metalloporphyrins gave mixtures of mono-β-alkylated chlorins and hydroxychlorins, whereas free-base porphyrins give meso- + β- mono- and dialkylated products. Reduction of N-substituted porphyrins with tosylhydrazine or sodium tetrahydroborate opened new routes to stable phlorins.