Heterotrimetallic paramagnetic complex of ring reduced tin(II) hexadecachlorophthalocyanine

Coordination complex (Cp*Cr-2(III))(+){CpFeII(CO)(2)(Sn-II[PcCl16](4-))}(-) (1) has been obtained by the reduction of tin(IV) dichloride hexadecachlorophthalocyanine (PcCl16) by decamethylchromocene (Cp*Cr-2) in the presence of {CpFeI(CO)(2)}(2). The process is accompanied by oxidation of CrII and FeI centers and the formation of paramagnetic CrIII and diamagnetic FeII species. Two-electron reduction of a macrocycle and the formation of diamagnetic [PcCl16](4-) as well as a transition of tin(IV) to tin(II) occur. The [PcCl16](4-) tetraanions are formed in (cryptand(K+))(2){(SnCl2)-Cl-IV[PcCl16](4-)}(2-)center dot 2C(6)H(4)Cl(2) (2) obtained by the reduction of SnIVPcCl16 by mild reductant - fullerene C-60 center dot(-) radical anions. Complexes 1 and 2 precipitate as crystals. Sandwich-type assemblies are formed in 1. Two (Cp*2CrIII)+ cations are sandwiched between two {CpFeII(CO)(2)(Sn-II[PcCl16](4-))}(-) planes, whereas layers of the {(SnCl2)-Cl-IV[PcCl16](4-)}(2-) macrocycles are formed in 2. The formation of the [PcCl16](4-) tetraanions in both 1 and 2 is supported by the data of structural analysis, optical spectroscopy and magnetic measurements. Susceptibility measurements correspond to the contribution of one non-interacting CrIII spin (S = 3/2) per formula unit. Weak antiferromagnetic coupling is observed between the spins. Only CrIII atoms contribute to EPR spectra of 1, whereas salt 2 is diamagnetic and EPR silent.