om050463j_si_001.pdf (193.04 kB)
[H(OEt2)2]+ and [Ph3C]+ Salts of the Borate Anions [B(CF3)4]-, [(CF3)3BCN]-, and [B(CN)4]-
journal contribution
posted on 2005-10-10, 00:00 authored by Maik Finze, Eduard Bernhardt, Michael Berkei, Helge Willner, Joyce Hung, Robert M. WaymouthThe reaction of gaseous HCl with K[B(CF3)4] in diethyl ether gave the oxonium acid
[H(OEt2)2][B(CF3)4] as a stable salt at room temperature. Syntheses of [Ph3C][B(CF3)4] and
[Ph3C][(CF3)3BCN] were accomplished from the corresponding potassium salts and Ph3CCl.
The metathesis reaction of Ag[B(CN)4] with trityl bromide resulted in formation of [Ph3C][B(CN)4]. Treatment of Cp2ZrMe2 with [H(OEt2)2][B(CF3)4], [Ph3C][B(CF3)4], [Ph3C][(CF3)3BCN], and [Ph3C][B(CN)4], monitored by NMR spectroscopy, showed the formation of
[Cp2ZrMe(OEt2)]+, [(Cp2ZrMe)2-μ-Me]+, [Cp2ZrMe]+, Cp2ZrMe{NCB(CF3)3}, and Cp2Zr{NCB(CN)3}2, respectively. Attempted polymerizations of propene with catalysts generated in situ
from rac-Et(1-Ind)2ZrMe2 and [H(OEt2)2][B(CF3)4], [Ph3C][B(CF3)4], or [Ph3C][B(CN)4] yielded
only little to no polymer, possibly due to the low solubility of the catalysts in the reaction
medium.
