PHOSPHINE COMPLEXES OF TI(III) AND ZR(III) - DETECTION IN SOLUTION BY EPR/ELECTROCHEMICAL METHODS

摘要

A comparative study by EPR is made on the electrolytic reduction of Cp(2)MX(2), Cp(2)M(CH3)(2), (Cp = eta(5)-C5H5, cyclopentadienyl ligand; M = Ti, Zr, X = Cl, Br) and Ind(2)Ti(CH3)(2) (Ind = eta(5)-C9H7, indenyl ligand) in the presence of phosphines. In the case of the dihalides, the monohalo(phosphines) were characterized. In the case of :he dimethyl compounds, Cp(2)M(CH3)(PMe(3)) and Ind(2)Ti(CH3)(PMe(3)) were identified at 230 K from their EPR spectra. At room temperature and for M = Ti, intramolecular rearrangement takes place to yield the presumably chelated dimethylphosphinomethyl compound Cp(2)Ti(III)CH(2)PMe(2) while Ind(2)Ti(CH3)(PMe(3)) remains stable. [References: 11]