P-H functionalised phosphinoalkoxides as ligands: synthesis and catalytic properties of [Cp2Zr(Me)(cyclo-1-O-2-PH(Tipp)-C6H10)] (Tipp=2,4,6-(Pr3C6H2)-C-i), [Cp2Zr(Me)(cyclo-1-O-2-PH(Tipp){Mo(CO)(5)}-C6H10)] and [Cp2Zr(BH4)(cyclo-1-O-2-PH(Mes)(BH3)-C6

摘要

The P-H functionalised phosphinoalcohol 1-PH(Tipp)-2-OH-cyclo-C6H10 (Tipp = 2,4,6-(Pr3C6H2)-C-i) reacts with [Cp2ZrMe2] with elimination of methane to give exclusively the mono-substituted product [Cp2Zr(Me)(cyclo-1-O-2-PH(Tipp)-C6H10)] (1), even at elevated temperature. 1 reacts with [Mo(CO)(5)(NMe3)] to give the heterodinuclear complex [Cp2Zr(Me)(cyclo-1-0-2-PH(Tipp){Mo(Co)(5)}-C6H10)] (2). The borane adduct [Cp2Zr(BH4)(cyclo-1-O-2-PH(Mes)(BH3)-C6H10)] (3, Mes = 2,4,6-Me3C6H2) was obtained from [Cp2Zr(BH4)(2)] and 1-PH(Mes)-2-OH-cyclo)-C6H10 in boiling hexane. 1-3 were characterised spectroscopically (H-1, C-13, P-31, B-11 (for 3), MS, and IR). A crystal structure determination of the R-C,R-C,R-P/S-C,S-C,S-P isomer of 1 was obtained. The complexes 1-3 were studied in the catalytic polymerisation of ethylene and propylene by activating them with methylalumoxane (MAO) as cocatalyst. (C) 2000 Elsevier Science S.A. All rights reserved. [References: 58]