Collect. Czech. Chem. Commun. 1990, 55, 2924-2932

The crystal, molecular structure and EPR spectrum of dipotassium bis[(μ-isothiocyanato-N,S)-(N-salicylidene-(R)-phenylalaninato)(N-salicylidene-(S)-phenylalaninato)]dicuprate(II)

Július Sivýa, František Pavelčíka, Juraj Krätsmár-Šmogrovičb, Milan Žemličkab and Valéria Seressováb

a Department of Analytical Chemistry
b Department of Inorganic and Organic Chemistry, Faculty of Pharmacy, Comenius University, 832 32 Bratislava


The title compound crystallizes in the triclinic system with a space group of P1 (No. 2); a = 0.8283(4), b = 0.9477(6), c = 1.2271(5) nm; α = 74.251(41), β = 82.351(34), γ = 70.475(40)°, V = 0.87282(74) nm3, Z = 1, F(000) = 432, μ = 1.624 mm-1, room temperature. The structure was refined to R = 0.0571 (Rw = 0.0568) for 1 920 observed reflections. The Cu(II) adopts a distorted square-pyramidal coordination. The base of the coordination polyhedron is formed by O(1), N(1), O(2) donor atoms of the terdentate Schiff-base dianion (sal-(R)-phe or sal-(S)-phe) and N(2) atom of the additional NCS- ligand. The axial site (apical position) of the pyramid is occupied by a weakly bonded S-atom; Cu-S = 0.2995(1) nm, originating from the -NCS- bridging ligands. Two units, [Cu(sal-(R)-phe)(NCS)]- and the corresponding (S)-form, are thus joined into centrosymmetric dicuprate complex anion; [Cu2(μ-isothiocyanato-N,S)2(sal-(R)-phe)(sal-(S)-phe)]2-. The Q-band EPR spectrum of this complex (powdered sample, room temperature) exhibits orthorhombic g components: gz = 2.234, gy = 2.059 and gx = 2.039 which can be interpreted as molecular ones (G = 4.9).