Inorganic Chemistry, Vol.41, No.5, 1170-1176, 2002
Synthesis, properties, and crystal structure of a novel anthracene-bridged molybdenum-zinc porphyrin dimer
The synthesis and properties of novel anthracene-bridged porphyrin dimers having an oxomolybdenum(V) porphyrin unit, H-2(DPA)[(MoO)-O-V(OMe)] (1) and (DPA)[(MoO)-O-V(OMe)][Zn-II(MeOH)] (2), and the relevant monomer porphyrin complexes (MoO)-O-V(MPP)OMe (3) and Zn-II(MPP) (4) are presented. An oxomolybdenum(V) unit was introduced into one of the two porphyrins in DPA to give 1, which has a free-base porphyrin unit. By introducing a zinc(II) ion to the free-base pan, a mixed-metal complex of 2 was prepared and isolated. The structure of 2 was analyzed by X-ray crystallography (2.7/6CH(2)Cl(2), triclinic, P (1) over bar (no. 2), a = 15.2854(12) AAngstrom b = 19.9640(15) Angstrom, c = 13.6915(12) Angstrom, alpha = 90.968(3)degrees, beta = 113.108(4)degrees, gamma = 96.501(4)degrees, Z = 2, R1 = 9.9, wR2 = 19.2). The structure of 2 demonstrated that a methanol is stably coordinated to the Zn(II) ion with the aid of a hydrogen bond to the methoxo ligand on the Mo(V) ion in the binding pocket of DPA. The electrochemical measurements of 2 suggested that the methanol was kept in the pocket of DPA in solution even at the reduced state of the molybdenum ion.