摘要:
The chiral N-functionalized cyclopentadiene ligand Cp(E)H (Cp(E) = C5H4CH(Ph)CH(Me)NMe(2)) was used for the preparation of a series of (transition) metal complexes. Metallation of Cp(E)H is accomplished by reaction with (n)BuLi, K or TlOEt. Reaction of Cp(E)Li with Me(3)SiCl and AlCl3 yields Cp(E)SiMe(3) and Cp(E)AlCl(2) respectively. In the aluminium compound a bidentate coordination of the Cp unit and the nitrogen side-arm is observed. Reaction of Cp(E)SiMe(3) with MCl(4) (M = Ti,Zr) affords Cp(E)MCl(3) in moderate yield. In Cp(E)TiCl(3) the nitrogen side-arm is only weakly coordinated, whereas in Cp(E)ZrCl(3) it is firmly coordinated to the metal centre. Moreover, Cp(E)ZrCl(3) behaves as a moderate Lewis acid, and hitherto catalyzes the Diels-Alder reaction between methacroleine and cyclopentadiene, albeit with no measurable enantiomeric excess.