examples of ansa-titanocenes derived from 1,2-bis(2-indenyl)ethane have been prepared. The titanium-mediated reductive coupling of 2-(hydroxymethyl)indenes provided a convenient method for substrate dimerization. Alkyl substitution of the indene ring at C(3) improved the regioselectivity of the reductive coupling to provide the ethylene bis(2-indenyl)ansa-ligands in 29–62% yield.
的新的例子安莎-titanocenes从1,2-双(2-
茚基)
乙烷已经制备的。
钛介导的2-(羟甲基)
茚的还原偶联为底物二聚化提供了一种方便的方法。在C(3)的
茚环的烷基取代改善了还原偶合的区域选择性,以提供亚乙基双(2-
茚基)安莎-ligands在29-62%的产率。