A stereogenic center at the position beta to the metallocene backbone is present in ferrocenyl ligands 2, which are interesting for asymmetric catalysis. These planar-chiral compounds are accessible for the first time by a highly diastereoselective and enantioselective synthesis (de=93-97 %; ee>/=96 %) from the ferrocenyl ketones 1. A variety of donor groups (E(1)=Ph(2)P small middle dotBH(3), SMe, SiPr; E(2)=SMe, STol, SePh, Ph(2)P small middle dotBH(3), iPr(2)P small middle dotBH(3)) can be introduced as electrophiles. Tol=tolyl=CH(3)C(6)H(4).
An efficient and flexible asymmetric synthesis of planar chiral ortho-functionalized ferrocenyl ketones in good overall yields (35−79%) and enantiomeric excesses (ee = 71−96%) is described. The key step of the procedure is the diastereoselective (de = 87−98%) orthometalation of ferrocenyl ketone
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