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, H2(DPA)[MoVO(OMe)] (1) and (DPA)[MoVO(OMe)][ZnII(MeOH)] (2), and the relevant monomer porphyrin
complexes MoVO(MPP)OMe (3) and ZnII(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 part, a mixed-metal complex of 2 was prepared and isolated. The structure of 2 was analyzed by
X-ray crystallography (2·7/6CH2Cl2, triclinic, P1̄ (no. 2), a = 15.2854(12) Å, b = 19.9640(15) Å, c = 13.6915(12)
Å, α = 90.968(3)°, β = 113.108(4)°, γ = 96.501(4)°, 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.