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

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 Me2 CpYPPh 2 (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 Me2 CpYS 2 PPh 2 (THF) ( 2 ) and Tp Me2 CpYSePPh 2 (THF) ( 4 Se ), respectively. Further investigations showed that the yttrium thiophosphinate Tp Me2 CpYSPPh 2 (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 ) 2 Y] + [Se 2 PPh 2 ] − ( 5 ) was obtained by a disproportionation process. The mechanism for the construction of the Ph 2 PE − and Ph 2 PE 2 − (E = S, Se) ligands has been discussed based on the in situ NMR experiments and some designed reactions. Rare-earth mediated oxidation and disproportionation of anionic phosphide ligand has been established by the reactions of yttrium phosphide with S or Se, providing a potential route to synthesize rare-earth mono- and di-thio/selenophosphinates.