New Schiff bases derived from chiral d‐camphor were determined to be effective phosphine ligands for the asymmetric palladium‐catalyzed allylic alkylation of activated methylene compounds, the allylic etherification of alcohols, and the allylic amination of primary amines or secondary amines, in which the corresponding products with various functional groups were achieved in good yields with excellent
Synthesis of highly rigid phosphine–oxazoline ligands for palladium-catalyzed asymmetric allylic alkylation
作者:Zhongxuan Qiu、Rui Sun、Dawei Teng
DOI:10.1039/c8ob02265h
日期:——
A highly rigid spiro phosphine–oxazoline ligand skeleton with a spirocarbon stereogenic center was developed from 7-bromo-1-indanone. The catalytic performance of the ligand was demonstrated in palladium-catalyzed asymmetric allylic alkylation. Under optimized conditions, high yields (up to 99%) and enantioselectivities (up to 99.9% ee) were obtained for reactions of 1,3-diphenylallyl acetates and
Tartrate-derivedbioxazolineligands, which form a five-membered chelate ring with metals, were evaluated for use in the asymmetric allylic alkylation (AAA) reactions of various symmetrical and unsymmetrical allylacetates. Excellent enantioselectivities were achieved by using both symmetrical and unsymmetrical allylacetates.
New P,N<sub>sp3</sub>ligands for palladium-catalyzed asymmetric allylic substitutions
作者:Qin Su、Chuan-Jin Hou、De-Quan Wei、Hao Qin、Ding-Hua Liang、Xiang-Ping Hu
DOI:10.1039/d3ob00519d
日期:——
New P,Nsp3 bidentate ligands containing two chiral carbon centers were developed and applied to palladium-catalyzedasymmetricallylicsubstitutionreactions. Good generalities with various nucleophiles, including carbon, nitrogen and oxygen containing nucleophiles, were achieved with up to 96% ee and 98% yield. This reaction provides an efficient method for the asymmetric formation of C–C, C–N and
开发了包含两个手性碳中心的新型 P,N sp3双齿配体,并将其应用于钯催化的不对称烯丙基取代反应。与各种亲核试剂(包括含碳、含氮和含氧的亲核试剂)的良好通用性达到了高达 96% 的 ee 和 98% 的产率。该反应为C-C、C-N和C-O键的不对称形成提供了一种有效的方法。
Synthesis of chiral S , N -thioimidazoline ligands for palladium-catalyzed asymmetric allylic alkylations
作者:Xin-Qi Hao、Ming-Zhan Shen、Ning-Ge Jian、Wei Pang、Xiao-Jing Shen、Xinju Zhu、Mao-Ping Song
DOI:10.1016/j.tetasy.2016.01.015
日期:2016.3
A series of chiral S,N-thioimidazoline ligands have been synthesized using 2-bromobenzoic acid or 1-bromo-2-naphthoic acid as starting materials. The obtained ligands were evaluated in the Pd-catalyzed asymmetric allylic alkylations and exhibited high catalytic efficiency: yields of up to 94% and enantioselectivities of up to 86% were achieved under the optimized conditions. (C) 2016 Elsevier Ltd. All rights reserved.