Oxidation and chalcogenylative disproportionation of anionic phosphide ligands in yttrium complexes with elemental sulfur and selenium

Abstract

The oxidation and disproportionation of anionic phosphide ligands in yttrium complexes with elemental sulfur and selenium are reported. The mixed Tp^Me2/Cp supported yttrium phosphide complex Tp^Me2CpYPPh₂(THF) (1) reacted with one equiv. of elemental S or Se in THF at room temperature to deliver two structurally characterized yttrium dithio- or monoseleno-phosphinates Tp^Me2CpYS₂PPh₂(THF) (2) and Tp^Me2CpYSePPh₂(THF) (4^Se), respectively. Further investigations showed that the yttrium thiophosphinate Tp^Me2CpYSPPh₂(THF) (4^S) can be isolated from the reactions of 2 and 1 or 1 and elemental S in a short reaction time. Moreover, after keeping 4^S or 4^Se in THF solution for some days, 2 or [(Tp^Me2)₂Y]⁺[Se₂PPh₂]⁻ (5) was obtained by a disproportionation process. The mechanism for the construction of the Ph₂PE⁻ and Ph₂PE₂⁻ (E = S, Se) ligands has been discussed based on the in situ NMR experiments and some designed reactions.