Kinetics and mechanisms of the formation of a sitting-atop complex of N-alkylporphyrin with Al(III) in moist acetonitrile

The formation of a sitting-atop complex of a N-alkylporphyrin, containing a 6-hydroxyhexyl group, with Al3+ was studied in moist acetonitrile by equil ibrium and kinetic measurements. A sandwich type of metalloporphyrin, where a metal ion binds two N-alkylporphyrins, appears to be formed under the co nditions that porphyrins exist in excess over a metal ion. When a large exc ess of metal ion was used, a 1:1 type of sitting-atop complex of Al(III) N- alkylporphyrin was produced through formation of the sandwich type of Al(II I) N-alkylporphyrin: Copyright (C) 2001 John Wiley & Sons, Ltd.