Process for the preparation of mono- and dimethylmetallocenes and their solutions especially for the use in the polymerisation of olefines.

摘要

The prodn. of methyl-transition metal cpds. of formula (Q)m(CpRa)(Cp'R'a')M(CH3)nX2-n (1) comprises reacting corresp. halo-transition metal cpds. (2) with Me3Al in a hydrocarbon solvent, opt. at elevated temp., adding alkali and/or alkaline earth metal fluoride (3) and removing the Al fluoride complex which is formed. In (1) Cp = cyclopentadienyl, indenyl or fluorenyl; R, R' = alkyl, phosphine, amine, alkyl-ether or aryl-ether gps. with O≤a≤5 and O≤a'≤5; Cp' = as for Cp. or Cp' = N with R = alkyl or aryl with a' = 1; Q = single- or multi-membered bridge -(ZR<1>R<2>)b- between Cp and Cp' (with R<1>, R<2> = H, 1-10C alkyl or 6-10C aryl; Z = C, Si or Ge; b = 1, 2 or 3); M = Gp. 3-6 transition metal, esp. Ti, Zr or Hf; X = halogen, pref. Cl or Br; n = 1 or 2; and m = 0 or 1. Pref. the reaction is carried out at 20-120 degrees C in opt. substd. aliphatic or aromatic hydrocarbons with b.pts. of 50-150 degrees C, using NaF or KF as the metal fluoride (3). The mole ratio of (2):(Me3Al):(3) = 1:1:1 in the case of mono-methyl cpds. (1), or 1:2:2 in the case of di-methyl cpds. (1).