A study of representative alcohol, alkoxide, thiol and thiolate complexes of B(C6F5)3; their roles as activators of zirconocene olefin polymerization initiators

The highly electrophilic borane B(C6F5)3 reacts with n-octadecanol (n-C18H37OH) and n-octadecanethiol (n-C18H37SH) to form equilibrium mixtures of reactants and the 1:1 adducts (n-C18H37EH)B(C6F5)3 (E=O, S); equilibrium constants for adduct formation are determined. The adducts are deprotonated by 1,8-bis(dimethylamino)naphthalene (proton sponge) to form the salts [C10H6(NMe2)2H][(n-C18H37O)B(C6F5)3] and [C10H6(NMe2)2H][(n-C18H37S)B(C6F5)3], respectively, and by Cp2ZrMe2 to give methane and, apparently, the unstable zirconium complexes [Cp2ZrMe][(n-C18H37E)B(C6F5)3]. The alcohol, alkoxide, thiol and thiolate systems are characterized in solution by 1H, 19F, 13C{1H} and 11B NMR spectroscopy and in the solid state by FAB mass spectrometry, and it is also shown that proton sponge can coordinate in monodentate fashion to B(C6F5)3.