具有平面手性和中心手性的新型二茂铁基配体的不对称合成

Asymmetric Synthesis of Novel Ferrocenyl Ligands with Planar and Central Chirality.

作者信息

Enders D, Peters R, Lochtman R, Raabe G

机构信息

Institut für Organische Chemie der RWTH Aachen, Professor-Pirlet-Strasse 1, D-52074 Aachen (Germany).

出版信息

Angew Chem Int Ed Engl. 1999 Aug;38(16):2421-2423.

PMID:10458809

Abstract

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).

摘要

茂金属主链β位的手性中心存在于二茂铁基配体2中，这些配体对于不对称催化很有意义。这些平面手性化合物首次可通过从二茂铁基酮1进行高度非对映选择性和对映选择性合成得到（非对映体过量率de = 93 - 97%；对映体过量率ee≥96%）。各种供体基团（E(1)=Ph₂P·BH₃、SMe、SiPr；E(2)=SMe、STol、SePh、Ph₂P·BH₃、iPr₂P·BH₃）可作为亲电试剂引入。Tol = 甲苯基 = CH₃C₆H₄ 。