versions as electron-rich neutral stereodirecting ancillary ligands for enantioselective transformations. Herein we demonstrate that cyclic (alkyl)(amino)carbene (CAAC) ligands can also engage in asymmetric transformations, thereby expanding the toolbox of available chiral carbenes.
Catalytic Asymmetric Boration of Acyclic α,β-Unsaturated Esters and Nitriles
作者:Ji-Eon Lee、Jaesook Yun
DOI:10.1002/anie.200703699
日期:2008.1
A Chiral 6-Membered <i>N</i>-Heterocyclic Carbene Copper(I) Complex That Induces High Stereoselectivity
作者:Jin Kyoon Park、Hershel H. Lackey、Matthew D. Rexford、Kirill Kovnir、Michael Shatruk、D. Tyler McQuade
DOI:10.1021/ol1021756
日期:2010.11.5
A chiral 6-membered annulated N-heterocyclic (6-NHC) copper complex that catalyzes β-borylations with high yield and enantioselectivity was developed. The chiral 6-NHC copper complex is easy to prepare on the gram scale and is very active, showing 10 000 turnovers at 0.01 mol % of catalyst without significant decrease of enantioselectivity and with useful reaction rates.
Six-membered N-Heterocyclic Carbene-based catalysts for asymmetric reactions
申请人:McQuade D. Tyler
公开号:US20110054170A1
公开(公告)日:2011-03-03
The present invention provides a catalyst complex or ligand, and compositions thereof, for use in a variety of organic reactions having high reactivity and enantioselectivity. The catalyst is a N-heterocyclic carbene having three fused rings with first and second rings being six-membered rings and the third being a five-membered ring. The first ring is fused to the second and has four substituents. The second ring has two nitrogens flanking a carbene atom with one nitrogen bound to a substituent. The carbene atom may optionally be bonded to a metal. The third ring is fused to the second ring and contains two nitrogens. The third ring of the catalyst has a double bond and two substituents on adjacent non-fused carbons. A non-fused nitrogen of the third ring is partially bonded to another substituent. Methods for the synthesis and use of the catalyst embodiments of the present invention are also provided.