“Box”ed in: A novel polysiloxane gel encapsulated CuII/bis(oxazoline) (CuII/Box) species was synthesized and used as a recyclable catalyst in the asymmetriccyclopropanation of alkenes with L‐menthyl diazoacetate.
在“框” ED:一种新颖的聚硅氧烷凝胶包封的Cu II /双(恶唑啉)(铜II /箱)物种合成并用作与烯烃的不对称环丙烷可回收催化剂大号-薄荷基重氮基。
Chiral Ruthenium(II)–Bis(2-oxazolin-2-yl)pyridine Complexes. Asymmetric Catalytic Cyclopropanation of Olefins and Diazoacetates
A chiral ruthenium(II)–bis(2-oxazolin-2-yl)pyridine catalyst prepared in situ from optically active bis(2-oxazolin-2-yl)pyridine (Pybox-ip) (2) and [RuCl2(p-cymene)]2 (1) exhibited efficient activity for the asymmetriccyclopropanation (ACP) of styrene and several diazoacetates to give the corresponding trans- and cis-2-phenylcyclopropane-1-carboxylates (3 and 4) in good yields (66—87%). A mixture
Cu(I)-Binaphthyldiimine Catalyzed Asymmetric Cyclopropanation of Olefin with Diazoacetate
作者:Hiroyuki Suga、Tomomi Fudo、Toshikazu Ibata
DOI:10.1055/s-1998-1824
日期:1998.8
Chiral 1,1′-binaphthyl-N,N′-bis(2,6-dichloro-benzy-lidene)-2,2′-diamine (1) was found to be an effective ligand for the copper-catalyzed enantioselective cyclopropanation of olefin with l-menthyl diazoacetate. For example, the reaction of 1,1-diphenylethylene with l-menthyl diazoacetate in the presence of CuOTf-1 complex in CH2Cl2 at -40 °C gave the corresponding cyclopropanecarboxylate in 98% ee.