Zirconocene dibromide

When two transannular linkers are present in an ansa-metallocene, they do not necessarily adopt positions that are adjacent to one another (in a 1,2-relationship). One such example of a nonadjacent complex was reported by Deck (9, Figure 4.6). This zirconocene dibromide has two tetramethyldis-iloxane bridges in a 1,3-relationship relative to one another. This complex was characterized by... 

Lofthus, O. W. Slebodnick, C. Deck, P. A. Electrophile-functionalized metallocene intermediates. Application in the diastereoselective synthesis of a tetramethyldisiloxane-bridged C2-symmetric ansa-zirconocene dibromide. Organometallics 1999,18, 3702-3708. 

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