Synthesis and Characterization of Phosphite-Containing Cobalt(III) Complexes Obtained via Disproportionation Reactions of Pentacoordinate Mononitrosyl Derivatives. Crystal Structure of trans-Bis(isothiocyanato)tetrakis(triethyl phosphite)cobalt(III) Tetraphenylborate

The disproportionation reactions of Co(SCN)2 (in the presence of P(OMe)3) and [Co(NCS)L3(NO)]+ (L = P(OEt)3 or PhP(OEt)2) species have been examined and have led to the synthesis of the first cobalt(III) complexes with the donor-atom set X2L4 (X = pseudohalogen; L = monodentate phosphite). Both the cis- and the trans-[Co(NCS)2L4]BPh4 isomers were isolated and characterized, and the crystal structure of trans-|Co(NCS)2[P(OEt)3]4)BPh4 was determined. Crystals are monoclinic, space group P21/c, with Z = 4 in a unit cell of the following dimensions: a = 19.05 (2) k,b= 13.25 (1) Å, c = 27.46 (3) Å, β = 109.86 (7)°. The structure was solved by the heavy-atom method from automated diffractometer data and refined to R = 0.0935 for 3199 reflections. © 1983, American Chemical Society. All rights reserved.