199111-56-3Relevant academic research and scientific papers
Disproportionation of cationic zirconium complexes: A possible pathway to the deactivation of catalytic cationic systems
Choukroun, Robert,Douziech, Bénédicte,Donnadieu, Bruno
, p. 5517 - 5521 (1997)
Protonolysis of the zirconium borohydride [(C5H4R)2Zr(BH4)2] (R = H, Me, SiMe3) with NHMe2PhBPh4 in THF leads to the corresponding cationic zirconium complex [(C5H4R)2Zr-(BH4)(THF)]BPh 4, and the structure of [(C5H4Me)2Zr(BH4)(THF)]BPh 4 was determined. In the presence of phosphine, PMe2Ph, the formation of the cationic hydride [(C5H4R)2ZrH-(PMe2Ph) 2]BPh4 is observed by 1H and 31P NMR followed by a disproportionation and a redox reaction with [BPh4]-, giving the neutral [(C5H4R)2ZrH(μ-H)]2 and the cationic ZrIII species [(C5H4R)2Zr(PMe2Ph) 2]BPh4 characterized by EPR spectroscopy and suggesting a probable pathway in the deactivation of cationic catalyst systems.
