An NMR study on the reaction of substituted dimethyl zirconocenes with dimethylanilinium borate

作者:Rocchigiani Luca; Bellachioma Gianfranco; Zuccaccia Cristiano; Macchioni Alceo*
来源:Journal of Organometallic Chemistry, 2012, 714: 32-40.
DOI:10.1016/j.jorganchem.2012.02.011

摘要

The reaction of a series of dimethyl zirconocenes [Me2Si(Cp)(2)ZrMe2, 1; Cp2t-buZrMe2, 2; Cp2n-buZrMe2, 3; Ind(2)ZrMe(2), 4; (Cp2ZrMe2)-Zr-Me4, 5; Cp*2ZrMe2, 6] with [HNMe2Ph][B(C6F5)(4)] was investigated by means of NMR spectroscopy. It was found that protonolysis of a Zr-Me group occurred generating a coordinative vacancy at the metal center and methane. Cations coming from 1-4 dimethyl precursors bound NMe2Ph, liberated from the protonation process, and formed zirconaaziridinium ion pairs {[Me2Si(Cp)(2)Zr(eta(2) -CH2NMePh)][B(C6F5)(4)], 7; [Cp2t-buZr(eta(2)-CH2NMePh)][B(C6F5)(4)], 8; [Cp2n-buZr(eta(2)-CH2NMePh)] [B(C6F5)(4)], 9; [Ind(2)Zr(eta(2)-CH2NMePh)][B(C6F5)(4)], 10}, reasonably as a consequence of CH activation of one Me group of coordinated NMe2Ph and methane elimination. The intramolecular/interionic structures and dynamics of 7e10 ion pairs were investigated by H-1, C-13 and F-19 1D-and 2D-NMR techniques. The reactions of 7 and 10 ion pairs with 2-methyl-1-heptene afforded stable diastereoisomeric ion pairs bearing a five-member azametallacycle.

  • 出版日期2012-9-1