Carbene‐Catalyzed Enantioselective Aromatic N‐Nucleophilic Addition of Heteroarenes to Ketones
作者:Yonggui Liu、Guoyong Luo、Xing Yang、Shichun Jiang、Wei Xue、Yonggui Robin Chi、Zhichao Jin
DOI:10.1002/anie.201912160
日期:2020.1.2
and optical purities. Our reaction involves the formation of an unprecedented aza-fulvene-type acylazolium intermediate. A broad range of N-heteroaromatic aldehydes and electron-deficient ketone substrates works effectively in this transformation. Several of the chiral N,O-acetal products afforded through this protocol exhibit excellent antibacterial activities against Ralstonia solanacearum (Rs) and
Nucleophilic β-Carbon Activation of Propionic Acid as a 3-Carbon Synthon by Carbene Organocatalysis
作者:Zhichao Jin、Ke Jiang、Zhenqian Fu、Jaume Torres、Pengcheng Zheng、Song Yang、Bao-An Song、Yonggui Robin Chi
DOI:10.1002/chem.201501481
日期:2015.6.22
Direct β‐carbonactivation of propionic acid (C2H5CO2H) by carbene organocatalysis has been developed. This activation affords the smallest azolium homoenolate intermediate (without any substituent) as a 3‐carbon nucleophile for enantioselective reactions. Propionic acid is an excellent raw material because it is cheap, stable, and safe. This approach provides a much better solution to azolium homoenolate
已经开发了通过卡宾有机催化作用对丙酸(C 2 H 5 CO 2 H)进行直接β-碳活化。这种活化提供了最小的均氮唑鎓中间体(无任何取代基),作为对映选择性反应的3碳亲核试剂。丙酸是便宜,稳定和安全的原料,因此是一种极好的原料。这种方法比以前建立的丙烯醛(没有任何取代基的烯醛)使用昂贵,不稳定且有毒的方法提供了更好的解决方案,用于合成均氮唑鎓。
Control of Enantioselectivity in Rhodium(I) Catalysis by Planar Chiral Dibenzo[<i>a</i>
,<i>e</i>
]cyclooctatetraenes
Planarchiral 5,11‐disubstiuted dibenzo[a,e]cyclo‐octatetraenes (dbCOTs) have been developed as the first useful chiral homologs to dbCOT‐ligands for asymmetric applications. Methods enabling the preparation of such compounds on a gram‐scale in enantiomerically pure form are described. Evaluated as ligands in rhodium(I)‐catalyzed 1,4‐ and 1,2‐arylation reactions, tertiary and quarternary stereogenic
The enantioselectivesynthesis of chiral N,N‐acetals derived from α‐dicarbonyl compounds has been achieved. Good yields and enantioselectivities were observed for the reaction with various α‐dicarbonyl compounds with 2‐aminobenzamides using chiral bis(imidazoline)‐phosphoric acid catalysts. Based on these experimental investigations, a possible transition state is proposed to explain the origin of
Cu-Catalyzed Esterification Reaction via Aerobic Oxygenation and C–C Bond Cleavage: An Approach to α-Ketoesters
作者:Chun Zhang、Peng Feng、Ning Jiao
DOI:10.1021/ja4085463
日期:2013.10.9
The Cu-catalyzed novel aerobic oxidativeesterification reaction of 1,3-diones for the synthesis of α-ketoesters has been developed. This method combines C-C σ-bond cleavage, dioxygen activation and oxidative C-H bond functionalization, as well as provides a practical, neutral, and mild synthetic approach to α-ketoesters which are important units in many biologically active compounds and useful precursors
已开发出用于合成 α-酮酯的 Cu 催化的新型 1,3-二酮有氧氧化酯化反应。该方法结合了 CC σ-键裂解、双氧活化和氧化 CH 键功能化,并为 α-酮酯提供了一种实用、中性和温和的合成方法,α-酮酯是许多生物活性化合物中的重要单元和各种有用的前体。功能组转换。在机理研究的基础上提出了一个合理的激进过程。