BIS(THIOPHOSPHINOYL)AMINES AND THEIR NEUTRAL COBALT(II) COMPLEXES, CONTAINING STABLE TETRAHEDRAL COS4 CORES - CRYSTAL-STRUCTURES OF NH(SPME2)(SPPH2) AND [CO((SPME2)(SPPH2)N)(2)]

The compound NH(SPMe2)(SPPh2) was prepared using a new method, ie. the reaction between Li[HN(S)PPh2] and Me2P(S)Cl in a diethyl ether-n-hex ane mixture. The complex [Co{(SPMe2)(SPPh2)N}(2)] was obtained by the reaction of CoCl2 . 6H(2)O and K[(SPMe2)(SPPh2)N] in methanol. The cry stal and molecular structure of both the free acid NH(SPMe2)(SPPh2) an d its cobalt (II) complex [Co{(SPMe2)(SPPh2)(2)N}(2)] were determined using X-ray diffractometry. The acid exhibits an anti conformation of the sulfur atoms in the SPNPS system and dimeric pairs are formed in t he crystal through N(1)-H(1)... S(2a) [2.43(9) Angstrom] hydrogen bond s, which involve only the sulfur atom of the S=PPh2 group of each mole cule. The cobalt complex consists of discrete, monomeric molecules, wi th isobidentate ligands [average Co-S 2.32(1), average P-S 2.031(5) An gstrom] and a distorted tetrahedral CoS4 core (S-Co-S range 102.7-117. 7 degrees). The structures of both the free acid and its cobalt (II) d erivative are discussed in relation with other bis(thiophosphinoyl)ami nes and metal complexes containing a CoS4 core.