Evidence of Fluoride Transfer from the Anion of [Zr{C₅H₃[SiMe₂(η¹‐NtBu)]₂}]⁺[RB(C₆F₅)₃]⁻ Complexes to the Zirconocenium Cation

Synthesis and reactivity of di(silylamido)cyclopentadienyl titanium and zirconium complexes

“…We have studied the reaction pathways followed when the alkyl-free cationic complexes [Zr{C 5 H 3 [SiMe 2 -(g 1 -NtBu)] 2 }][RB(C 6 F 5 ) 3 ] are heated in the absence or presence of triphenylphosphane [19]. Complexes 30 and 32 were thermally stable upon heating their solutions for several hours up to 80°C.…”

“…Quantitative C 6 F 5 transfer was complete after 12 h to give 34 as the unique reaction product, isolated as a crystalline solid. The molecular structure of 34 was determined by diffraction methods [19].…”

“…In addition, heating an equimolar mixture of 30 and PPh 3 to 50°C for 7 days gave a mixture from which a colourless monocrystal identified as complex 35 was isolated [19]. The molecular structure of this compound from X-ray diffraction studies revealed that it contained a separate l-F bridged dinuclear cation [(Zr{C 5 H 3 [SiMe 2 (g 1 -N t Bu)] 2 }) 2 F] + and the free B(C 6 F 5 ) 3 Bz À anion (Fig.…”

“…When a mixture of equimolar amounts of 32 and PPh 3 was heated at 80°C for 7 days crystals of the zwitterionic compound 36 suitable for X-ray diffraction studies were isolated [19]. The molecular structure of compound 36 (Fig.…”

“…These doubly silyl-bridged group 4 metal amido chelates [17][18][19] activated with MAO are efficient catalysts for ethene polymerization despite generating alkyl-free 14-electron d 0 cationic species.…”