Alkene Hydrogenation with Titanium and Zirconium Catalysts

3 Alkene Hydrogenation with Titanium and Zirconium Catalysts 

Buchwald and coworkers have used the titanium version of the Brintzinger catalyst (2.100) in the asymmetric reduction of trisubstituted alkenes. The catalyst is reduced in situ to a titanium(lll) hydride species (see Section 3.6). The reduction is achieved with butyllithium and hydrogen, whilst the silane serves to stabihse 

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