SYNTHETIC HEMES AS MIMICS FOR HIGH-VALENT INTERMEDIATES IN HEMOPROTEIN CATALYZED OXIDATIONS - SYNTHESIS AND OXIDATION OF CHLORO-7,8,17,18-TETRACYANO-5,10,15,20-TETRAPHENYLPORPHYRINATOIRON(III), A HEME WHICH CONTAINS STRONGLY ELECTRON-WITHDRAWING GROUPS IN THE BETA-PYRROLE POSITIONS

The haem chloro-7,8,17,18-tetracyano-5,10,15,20-tetraphenylporphyrinato-iron(III), which contains strongly electron withdrawing groups in the beta-pyrrole positions, has been synthesised as a possible substrate for oxidations which mimic the formation of high valent haems in peroxidase and cytochrome p-450 catalysed reactions. The porphyrin was synthesised by reacting the copper(II) complex of the corresponding tetrabromoporphyrin with CuCN in quinoline. Treatment of the haem with m-chloroperbenzoic acid gave an oxidation product which is stable in solution at room temperature.