Preparation and redox properties of phosphite derivatives of R 2C 2Co 2(CO) 6− n[P(OMe) 3] n (R=CF 3, MeO 2C)

Abstract

A series of phosphite complexes R 2C 2Co 2(CO) 6− n [P(OMe) 3] n (R=CF 3, MeO 2C), n=1–4, have been prepared and characterised. Cyclic and square-wave voltammetry shows that the kinetic stability of the radical cations increases with substitution and when R=CF 3. The radical cation {(CF 3) 2C 2Co 2(CO) 2[P(OMe) 3] 4}PF 6 4a + has been characterised and its crystal structure compared with that of the neutral parent. Analysis of the anisotropic ESR spectrum of 4a + is consistent with an unpaired electron in a SOMO with little d z 2 character.