Dianionic Titanyl and Vanadyl (Cation ) [M O(Pc )] Phthalocyanine Salts Containing Pc Macrocycles.

In this study, the titanyl and vanadyl phthalocyanine (Pc) salts (Bu N ) [M O(Pc )] (M=Ti, V) and (Bu MeP ) [M O(Pc )] (M=Ti, V) with [M O(Pc )] dianions were synthesized and characterized. Reduction of M O(Pc ) carried out with an excess of sodium fluorenone ketyl in the presence of Bu N or Bu MeP is exclusive to the phthalocyanine centers, forming Pc species. During reduction, the metal +4 charge did not change, implying that Pc is an non-innocent ligand. The Pc negative charge increase caused the C-N(pyr) bonds to elongate and the C-N(imine) bonds to alternate, thus increasing the distortion of Pc. Jahn-Teller effects are significant in the [eg(π*)] dianion ground state and can additionally distort the Pc macrocycles. Blueshifts of the Soret and Q-bands were observed in the UV/Vis/NIR when M O(Pc ) was reduced to [M O(Pc )] and [M O(Pc )] . From magnetic measurements, [Ti O(Pc )] was found to be diamagnetic and (Bu N ) [V O(Pc )] and (Bu MeP ) [V O(Pc )] were found to have magnetic moments of 1.72-1.78 μ corresponding to an S=1/2 spin state owing to V electron spin. As a result, two latter salts show EPR signals with V hyperfine coupling.