Cobalt-Catalyzed Enantioselective Intramolecular Hydroacylation of Ketones and Olefins
摘要:
Cobalt-chiral diphoshine catalytic systems promote intramolecular hydroacylation reactions of 2-acylbenzaldehydes and 2-alkenylbenzaldehydes to afford phthalide and indanone derivatives, respectively, in moderate to good yields with high enantioselectivities. The ketone hydroacylation did not exhibit a significant H/D kinetic isotope effect (KIE) with respect to the aldehyde C-H bond, indicating that C-H activation would not be involved in the rate-limiting step.
A nickel-catalyzed asymmetric Suzuki–Miyaura cross-coupling of racemic 3-bromo-phthalides and arylboronic acids was realized for the synthesis of diverse chiral 3-aryl-phthalides in moderate to excellent reaction yields. The reaction proceeded in a stereoconvergent manner and high enantioselectivities were observed for most examined examples. A number of functional groups like aldehyde, ester and bromide
Binaphthyl–prolinol chiral ligands: design and their application in enantioselective arylation of aromatic aldehydes
作者:Chao Yao、Yaoqi Chen、Ruize Sun、Chao Wang、Yue Huang、Lin Li、Yue-Ming Li
DOI:10.1039/d1ob00289a
日期:——
Binaphthyl–prolinol ligands were designed and applied in enantioselective arylation of aromatic aldehydes and sequential arylation–lactonization of methyl 2-formylbenzoate. Under optimized conditions, the reactions provided the desired diarylmethanols and 3-aryl phthalides in up to 96% yields with up to 99% ee and up to 89% yields with up to 99% ee, respectively. In particular, essentially optically
联萘-脯氨醇配体被设计并应用于芳香醛的对映选择性芳基化和2-甲酰基苯甲酸甲酯的顺序芳基化-内酯化。在优化的条件下,反应分别以高达 96% 的产率和高达 99% 的 ee 和高达 89% 的产率和高达 99% 的 ee 提供了所需的二芳基甲醇和 3-芳基苯酞。特别是,通过重结晶大量获得了基本上光学纯的 3-芳基苯酞(超过 99% ee)。
Rhodium(III)-Catalyzed Asymmetric Addition of Inert Arene C–H Bond to Aldehydes To Afford Enantioenriched Phthalides
作者:Wenkun Chen、Jie Li、Hui Xie、Jun Wang
DOI:10.1021/acs.orglett.0c01052
日期:2020.5.1
An asymmetric rhodium(III)-catalyzed Grignard-type addition of inert arene C-H bond to aldehydes is reported. It provides a new strategy for the synthesis of chiral 3-substituted phthalides in good yields (up to 87%) with high enantiomeric purity (up to 99% ee). Interestingly, a chiral-matching effect between substrate and catalyst was observed, which is crucial to accomplish satisfied reaction outcomes
Catalytic asymmetric 1,2-Addition/Lactonization tandem reactions for the syntheses of chiral 3-Substituted phthalides using organozinc reagents
作者:Huayin Huang、Yabai Wang、Hua Zong、Ling Song
DOI:10.1002/aoc.4643
日期:2019.1
Using chiral phosphoramide ligand 2d‐Zn (II) complex derived from (1R,2R)‐1,2‐diphenylethylenediamine as the catalyst, we have developed efficient catalytic asymmetric 1,2‐addition/lactonization tandem reactions of diverse organozinc reagents with varied methyl 2‐formylbenzoates for the construction of optically enriched 3‐aryl or alkyl substituted phthalides, which are significant building blocks
Diastereomeric Aziridine Carbinol Catalyzed Enantioselective Arylation Reaction: Toward the Asymmetric Synthesis of Both Enantiomers of Chiral 3-Aryl Phthalide
The diastereomeric aziridine carbinols are applied, respectively, as efficient chiral ligand in the catalysis of asymmetric arylation and sequential arylation-lactonization cascade. The two diastereomers, which are facilely synthesized from the same chiral source, function as pseudo enantiomers in arylation of aromatic aldehydes providing the different enantiomers of the diarylmethanols with almost the same excellent enantioselectivities. The arylation method is also carried out in tandem with lactonization process to afford a concise synthetic approach to both enantiomers of optically active 3-aryl phthalide.