Complexes of transition metal carbonyl clusters with tin(II) phthalocyanine in neutral and radical anion states: methods of synthesis, structures and properties.

Coordination of tin(II) phthalocyanine to transition metal carbonyl clusters in neutral {Sn II (Pc 2- )} 0 or radical anion {Sn II (Pc˙ 3- )} - states is reported. Direct interaction of Co 4 (CO) 12 with {Sn II (Pc 2- )} 0 yields a crystalline complex {Co 4 (CO) 11 ·Sn II (Pc 2- )} (1). There is no charge transfer from the cluster to phthalocyanine in 1, which preserves the diamagnetic Pc 2- macrocycle. The Ru 3 (CO) 12 cluster forms complexes with one or two equivalents of {Sn II (Pc˙ 3- )} - to yield crystalline {Cryptand[2.2.2](Na + )}{Ru 3 (CO) 11 ·Sn II (Pc˙ 3- )} - (2) or {Cryptand[2.2.2](M + )} 2 {Ru 3 (CO) 10 ·[Sn II (Pc˙ 3- )] 2 } 2- ·4C 6 H 4 Cl 2 (3) (M + is K or Cs). Paramagnetic {Sn II (Pc˙ 3- )} - species in 2 are packed in π -stacking [{Sn II (Pc˙ 3- )} - ] 2 dimers, providing strong antiferromagnetic coupling of spins with exchange interaction J / k B = -19 K. Reduction of Ru 3 (CO) 12 , Os 3 (CO) 12 and Ir 4 (CO) 12 clusters by decamethylchromocene (Cp* 2 Cr) and subsequent oxidation of the reduced species by {Sn IV Cl 2 (Pc 2- )} 0 yield a series of complexes with high-spin Cp* 2 Cr + counter cations ( S = 3/2): (Cp* 2 Cr + ){Ru 3 (CO) 11 ·Sn II (Pc˙ 3- )} - ·C 6 H 4 Cl 2 (4), (Cp* 2 Cr + ){Os 3 (CO) 10 Cl·Sn II (Pc˙ 3- )} - ·C 6 H 4 Cl 2 (5) and (Cp* 2 Cr + ){Ir 4 (CO) 11 ·Sn II (Pc˙ 3- )} 2 - (6). It is seen that reduced clusters are oxidized by Sn IV , which is transferred to Sn II , whereas the Pc 2- macrocycle is reduced to Pc˙ 3- . In the case of Os 3 (CO) 12 , oxidation of the metal atom in the cluster is observed to be accompanied by the formation of Os 3 (CO) 10 Cl with one Os I center. Rather weak magnetic coupling is observed between paramagnetic Cp* 2 Cr + and {Sn II (Pc˙ 3- )} - species in 4, but this exchange interaction is enhanced in 5 owing to Os 3 (CO) 10 Cl clusters with paramagnetic Os I ( S = 1/2) also being involved in antiferromagnetic coupling of spins. The formation of {Sn II (Pc˙ 3- )} - with radical trianion Pc˙ 3- macrocycles in 2-5 is supported by the appearance of new absorption bands in the NIR spectra and essential N meso -C bond alternation in Pc (for 3-5). On the whole, this work shows that both diamagnetic {Sn II (Pc 2- )} 0 and paramagnetic {Sn II (Pc˙ 3- )} - ligands substitute carbonyl ligands in the transition metal carbonyl clusters, forming well-soluble paramagnetic solids absorbing light in the visible and NIR ranges.