Control of reactivity at the porphyrin periphery by metal ion co-ordination: a general method for specific nitration at the β-pyrrolic position of 5,10,15,20-tetra-arylporphyrins
Abstract
The site of nitration by nitrogen dioxide on a range of metalloporphyrins has been found to be dependent on the co-ordinated metal; copper(II), nickel(II), and palladium(II) complexes are nitrated specifically on the porphyrin β-pyrrolic position while magnesium(II), zinc(II), chloroiron(III), and cobalt(II) complexes also give products which result from reaction at the meso-position.