title: Formation of dinuclear titanium and zirconium complexes by olefin metathesis--catalytic preparation of organometallic catalyst systems.
abstract: The titanium complex [(C(5)H(4)bond;allyl)TiCl(3)] (2) undergoes olefin metathesis coupling when treated with 3 mol % of [Cl(2)(L(1))(L(2))Ru=CHPh] (L(1)=L(2)=PCy(3), 4 a; L(1)=PCy(3), L(2)=(H(2)IMes), 4 b) to yield the dimetallic complex [Cl(3)Ti(C(5)H(4))-CH(2)CH=CHCH(2)-(C(5)H(4))TiCl(3)] (5). The allyl-substituted titanocene complex [Cp(C(5)H(4)bond;allyl)TiCl(2)] (3) analogously yields the dimetallic system 6 when treated with 4. The ansa-zirconocene complex [Me(2)Si(C(5)H(4))(C(5)H(3)bond;allyl)ZrCl(2)] (7) cleanly yields the analogous dimetallic coupling product 8 (>95 % isomerically pure), when treated with catalytic amounts of 4 b in toluene. Complex 8 gives an active homogeneous ethene or propene polymerization catalyst, especially at elevated temperatures, when treated with excess methylalumoxane.
authors.affiliation: Organisch-Chemisches, Institut der Universität Münster, Corrensstrasse 40, 48149 Münster, Germany.
authors.forename: Jesus
authors.initials: J
authors.lastname: Cano Sierra
authors.forename: Doris
authors.initials: D
authors.lastname: Hüerländer
authors.forename: Michael
authors.initials: M
authors.lastname: Hill
authors.forename: Gerald
authors.initials: G
authors.lastname: Kehr
authors.forename: Gerhard
authors.initials: G
authors.lastname: Erker
authors.forename: Roland
authors.initials: R
authors.lastname: Fröhlich