Structure elucidation of dicarboxylate complex of SnIV porphyrin with a ring current effect model

Abstract

A new simple model of porphyrin ring current effect was proposed based on a line current approximation. It can reproduce the porphyrin-induced shifts for several Sn(IV)(tpp) and Sn(IV)(oep) dicarboxylate complexes quite satisfactorily. Perpendicular arrangement of the aromatic rings in the diaromatic-carboxylate complexes of Sn(IV)(tpp) and Sn(IV)(oep) was clarified with this porphyrin ring current effect model. There are two structures, exo and endo, in solution in dinaphthalene-1- and 2- carboxylate complexes of Sn(IV)(tpp) and Sn(IV)(oep). The exo conformer is in dynamic equilibrium with the endo form in solution. Thermodynamic data of these conformational equilibria are given. © 2006 Elsevier Ltd. All rights reserved.