A SULFUR-CAPPED TRIANGULAR COBALT-TRIBUTYLPHOSPHINE-AMINOBENZENETHIOLATO COMPLEX - SYNTHESIS, STRUCTURE AND PROPERTIES OF CO-3(MU(3)-S)(ABT)(3)(PBU3N)(3)

The reaction of CoCl2, Habt (2-aminobenzenethiol), NaOMe and PBu3n (tr ibutylphosphine) in an equimolar ratio under anaerobic conditions, fol lowed by the addition of an excess of Li2S led to the triangular clust er complex Co-3(mu(3)-S)(abt)(3)(PBu3n)(3). It crystallizes in the tri clinic space group P (1) over bar, with a=13.231(2), b=14.201(2), c=18 .890(2) Angstrom, alpha=79.970(10)degrees, beta=87.560(10)degrees, gam ma=67.040(1)degrees, V=3216.6(12) Angstrom(3) and Z=2. The molecule co nsists of three ''Co(abt)(PBu3n)'' units with the Co-3 plane capped by the bridging mu(3)-S atom to form an approximately equilateral triang le with an average Co-Co distance of 2.709 Angstrom. The cobalt atoms located in distorted trigonal-bipyramidal environments are further bri dged by mu(2)-S atoms from the three abt ligands and terminally coordi nated by N and P donors. The cyclic voltammogram showed three quasi-re versible redox processes with E-1/2=0.79, -0.07, and -0.81 V, vs. SCE. The variable-temperature magnetic susceptibility measurements showed an antiferromagnetic exchange interaction within the triangular spin c luster.