Asymmetric Intermolecular Boron Heck-Type Reactions via Oxidative Palladium(II) Catalysis with Chiral Tridentate NHC-Amidate-Alkoxide Ligands
作者:Kyung Soo Yoo、Justin O’Neill、Satoshi Sakaguchi、Richard Giles、Joo Ho Lee、Kyung Woon Jung
DOI:10.1021/jo901977n
日期:2010.1.1
Chiral dimeric tridentate NHC-amidate-alkoxide palladium(II) complexes, 3a and 3b, effected oxidative boron Heck-type reactions of aryl boronicacids with both acyclic and cyclic alkenes at room temperature to afford the corresponding coupling products with high enantioselectivities. The high degree of enantioselection, far superior to existing methods, stems from differences in the nonbonding interactions
N-HETEROCYCLIC CARBENE-AMIDO PALLADIUM(II) CATALYSTS AND METHOD OF USE THEREOF
申请人:Jung Kyung Woon
公开号:US20100036131A1
公开(公告)日:2010-02-11
A new N-heterocyclic catalyst system which contains N-heterocyclic carbene and amido as ligands, which are strongly bound to a palladium metal. Another heteroatom functionality can be used as a third ligand L. The NHC-amidate ligand system is unique in structure, and shows excellent reactivities in a number of chemical reactions. The chemical reactions include carbon-carbon and carbon-heteroatom (oxygen and nitrogen) bond formations, and oxidation reactions of saturated carbon chemicals via C—H activation.
Herein, we report an asymmetric intermolecular Heck-type reaction of acyclic alkenes by using a palladium-pyridinyl oxazoline diacetate complex under oxidativepalladium(II) catalysis conditions. A premade palladium-ligand complex afforded higher enantioselectivities than a corresponding premixed palladium-ligand system, while offering enhanced asymmetric induction when compared to known intermolecular