The structures and thermal rearrangements of alkylated palladium and copper corroles

Abstract

The kinetically controlled alkylation of palladium corrole ambident anions occurs both at the nitrogen atom (N-21) of ring A and at a peripheral carbon atom (C-3). Variation in solvent, from dipolar aprotic to strongly hydrogenbonding, allowed some control of the C:N alkylation product ratio. The palladium 2,3,7,8,12,13,17,18,21-nonaalkylcorroles underwent thermal isomerisation to the palladium 2,3,3,7,8,12,13,17,18-nona-alkylcorroles. Alkylation of copper corrole ambident anions occurs only at N-21 and the resulting copper 2,3,7,8,12,13,17,18,21-nonaalkylcorroles do not undergo thermal rearrangement; instead, thermal cleavage of the N-alkyl linkage occurs to give the parent copper corroles.