通过使用手性铁络合物作为催化剂,使用N-保护的氨基酸(AAs)作为大分子配体,描述了使用水为H 2 O 2的α-取代的苯乙烯的高度对映选择性环氧化。氨基酸与铁中心协同作用,以促进H 2 O 2的有效活化,从而在较短的反应时间内以良好的收率和立体选择性(高达97%ee)催化这种具有挑战性的底物的环氧化 。
The highlyenantioselectivehydrovinylation of alpha-alkyl vinylarenes was realized by using nickel complexes of chiral spiro phosphoramidite ligands. The method provided a new approach to the construction of chiral all-carbon quaternary centers.
Mechanisms of elimination reactions. 39. Steric and electronic effects on stereochemistry in eliminations from primary alkyltrimethylammonium salts
作者:Brent R. Dohner、William H. Saunders
DOI:10.1021/ja00262a010
日期:1986.1
Les resultats montrent que l'elimination syn a un etat de transition plus carbamonique que l'elimination ante
Les resultat montrent que l'elimination syn a un etat de transition plus carbamonique que l'elimination ante
Iridium-Catalyzed Asymmetric Transfer Hydrogenation of 1-Aryl-1-alkylethenes with Ethanol
作者:Xixia Tang、Lu Qian、Guixia Liu、Zheng Huang
DOI:10.1021/acs.orglett.3c01880
日期:2023.7.7
Asymmetric transfer hydrogenation of 1-aryl-1-alkylethenes with ethanol was developed with a chiral (PCN)Ir complex as the precatalyst, featuring high enantioselectivities, good functional group tolerance, and operational simplicity. The method is further applied to formal intramolecular asymmetric transfer hydrogenation of alkenols without an external H-donor, producing a tertiary stereocenter and
以手性(PCN)Ir配合物为预催化剂,开发了1-芳基-1-烷基乙烯与乙醇的不对称转移氢化反应,具有对映选择性高、官能团耐受性好、操作简单等特点。该方法进一步应用于无需外部氢供体的烯醇的正式分子内不对称转移氢化,同时产生叔立构中心和远程酮基。克级合成和( R )-黄根醇关键前体的合成凸显了催化系统的实用性。
Verfahren zur Herstellung von substituierten Styrolen
申请人:BAYER AG
公开号:EP0197274A1
公开(公告)日:1986-10-15
Substituierte Styrole werden hergestellt durch Behandlung von N-Acyl-ß-phenethylaminen mit Basen und Abdestillieren des während der Reaktion gebildeten Styrols.