The synthesis and characterization of cobalt complexes with diphosphorus–sulphur and –selenium cyclic units as trihapto ligands. X-Ray crystal structures of [Co{CMe(CH2PPh2)3}(P2X)]BF4·C6H6(X = S or Se)
Abstract
The reaction of Co(BF4)2·6H2O with P4S3 or P4Se3 in the presence of 1,1,1-tris(diphenylphosphino methyl)ethane (tppme) yielded complexes [Co(tppme)(P2X)]BF4·C6H6[X = S (1) or Se (2)]. The molecular structures of the complexes have been determined by single-crystal X-ray diffraction methods. Both compounds crystallize in the monoclinic space group P21/n with Z= 4 and unit-cell dimensions: a= 17.193(7), b= 20.164(8), c= 13.136(7)Å, β= 103.35(8)°[for (1)]; and a= 17.049(8), b= 20.119(9), c= 13.188(8)Å, β= 102.74(8)°[for (2)]. The metal atom in both compounds is in a six-co-ordinate environment formed by the tppme P atoms and by the atoms of the heterocyclic P2S or P2Se unit, as shown by the crystallographic investigations and by 31P n.m.r. studies.