Synthesis, Spectral Characterisation and Crystal Structure of (1,24-Bicyclophthalocyaninato)bismuth(III)

Abstract

A new orange bicyclophthalocyanine complex of bismuth(III), [Bi(C48H24N13)], has been synthesised by means of the template reaction of bismuth(III) acetate with phthalodinitrile. The ligand consists of the phthalocyanine skeleton, which is bridged by two additional isoindole units. The conjugation of the phthalocyanine ring is interrupted by the two bridgehead sp3-hybridised carbon atoms. The main difference between this new bicyclophthalocyanine and those previously reported in the literature lies in the position of the bridgehead carbon atoms. In order to differentiate between these bicyclophthalocyaninato complexes, we propose a nomenclature: [Bi(C48H24N13)] is named Bi(1,24-Pcc), and the other bicyclic ligands already reported in the literature are named (1,16-Pcc) and (1,17-Pcc). The molecular structure of Bi(1,24-Pcc) shows the coordination polyhedron around the bismuth atom, made up of the six isoindole nitrogen atoms of the macrocycle, as a strongly distorted trigonal prism. The two Bi−Niso bonds of the bridge and two of the four Bi−Niso bonds of the (Pc) ring have bond lengths between 2.40 and 2.47 A. One of the remaining bonds is longer (2.55 A), and the sixth has a very short length of 2.20 A. This new complex was fully characterised by UV/Vis and IR spectroscopy, also reported here.