A Nearly Linear Single Hydroxo Bridge. Synthesis, Structure, and Magnetic Susceptibility of (μ-Hydroxo)bis((tetraphenylporphinato)manganese(III)) Perchlorate

The synthesis, X-ray structure, and magnetic susceptibility characterization of a hydroxo-bridged complex, (μ-hydroxo)bis((tetraphenylporphinato)manganese(III)) perchlorate, {[Mn-(TPP)]2(OH)}ClO4, are described. The complex is readily prepared by a controlled hydrolysis of monomeric diaquo(tetraphenylporphinato)manganese(III) perchlorate. Interestingly, the bridging hydroxo complex appears to be more stable than the putative μ-oxo complex in halocarbon solvents. The X-ray structure determination shows a complex in which two five-coordinate manganese(III) ions are bridged by a single hydroxo ligand with an average Mn−O distance of 2.026(1) A and a Mn−O(H)−Mn bridge angle of 160.4(8)°. The two porphyrin planes are nearly coplanar, and the two metal ions are separated by 3.993 A. The average Mn−NP distance is 2.008(7) A. The two manganese ions are displaced by 0.19 and 0.20 A from their respective 24-atom mean planes. Both of the two porphyrin rings are moderately S4 ruffled and have a near-staggered orienta...