Polymer-Supported 2,2′-Bis(oxazolin-2-yl)-1,1′-binaphthyls (Boxax): Immobilized Chiral Ligands for Asymmetric Wacker-Type Cyclizations
作者:Yasuhiro Uozumi、Heiko Hocke
DOI:10.1055/s-2002-35603
日期:——
,1'-binaphthyl (boxax) ligands were anchored on various polymer supports including PS-PEG, PS, PEGA, and MeO-PEG via selective monofunctionalization at the 6-position of the binaphthyl backbone. Palladium(II) complexes of the supported boxax ligands catalyzed Wacker-type cyclization of 2-(2,3-dimethyl-2-butenyl)phenol to give 2-methyl-2-isopropenyl-2,3-dihydrobenzofuran with up to 96% ee.
同手性 2,2'-双(恶唑啉-2-基)-1,1'-联萘 (boxax) 配体通过 6 位选择性单官能化锚定在各种聚合物载体上,包括 PS-PEG、PS、PEGA 和 MeO-PEG -联萘骨架的位置。负载型 boxax 配体的钯 (II) 配合物催化 2-(2,3-二甲基-2-丁烯基)苯酚的瓦克型环化反应,生成 2-甲基-2-异丙烯基-2,3-二氢苯并呋喃,含量高达 96% ee。