METHOD OF SYNTHESIS OF BRIDGE METALLOCENE COMPOUND, BRIDGE BIS-CYCLOPENTADIENYL LIGAND Russian patent published in 2001 - IPC

FIELD: organometallic compounds. SUBSTANCE: invention proposes stereoselective method of synthesis of bridge (having bridge bond) chiral metallocenes of the formula (IV) by synthesis of silyl-, germyl- or stannyl-substituted ligands of the formula (II) or (III) . Method involves the following stages: a) interaction of ligand of the formula (I) with compound that is able to form delocalized anion in each cyclopentadienyl group with formation of corresponding doubled anion; b) interaction of doubled anion with compound ZR₃Q or (ZR₂)_mQ where Z is Si, Ge, Sn; R is C₁-C₁₀-alkyl; Q is halogen atom; m = 1 or 2 with formation of mixture of rac- and meso-form of Z-substituted bridge bis- -cyclopentadienyl ligand of the formula (II) or (III); c) if necessary, method involves separation of moiety of one of isomeric form of Z-substituted bridge bis-cyclopentadienyl ligand; d) interaction of Z-substituted bridge bis-cyclopenta- -dienyl ligand with compound of transient metal MX where M is Ti, Zr, Hf; X means halogen atom to yield metallocene of the formula (IV). Reaction is carried out in liquid dispersing agent that does not coordinate the compound of transient metal. EFFECT: increased yield, improved purity of rac- and meso-form of bridge metallocenes. 13 cl, 24 ex