Lewis Acid Enabled Copper-Catalyzed Asymmetric Synthesis of Chiral β-Substituted Amides
作者:Mamen Rodríguez-Fernández、Xingchen Yan、Juan F. Collados、Paul B. White、Syuzanna R. Harutyunyan
DOI:10.1021/jacs.7b07344
日期:2017.10.11
are able to overcome the reactivity issues of unactivated enamides, known as the least reactive carboxylic acid derivatives, toward alkylation with organomagnesium reagents. Allowing unequaled chemo-reactivity and stereocontrol in catalytic asymmetric conjugate addition to enamides, the method is distinguished by its unprecedented reaction scope, allowing even the most challenging and synthetically
在这里,我们报告说,容易获得的基于甲硅烷基和硼的路易斯酸与手性铜催化剂结合能够克服未活化的烯酰胺(被称为反应性最低的羧酸衍生物)对有机镁试剂进行烷基化的反应性问题。在催化不对称共轭加成到烯酰胺中允许无与伦比的化学反应性和立体控制,该方法以其前所未有的反应范围而著称,即使是最具挑战性和合成上重要的甲基化也能以良好的产率和出色的对映选择性完成。该催化协议可耐受较宽的温度范围(-78 °C 至环境温度)和放大(10 g),而手性催化剂可以重复使用而不会影响整体效率。
A Novel and Efficient Method for the Preparation of α-Hydroxyimino Carbonyl Compounds from α,β-Unsaturated Carbonyl Compounds with Butyl Nitrite and Phenylsilane Catalyzed by a Cobalt(II) Complex
作者:Koji Kato、Teruaki Mukaiyama
DOI:10.1246/bcsj.64.2948
日期:1991.10
Various α,β-unsaturated carbonylcompounds, such as α,β-unsaturated esters, α,β-unsaturated ketones, α,β-unsaturated nitriles, and α,β-unsaturated amides, were directly converted to the corresponding a-hydroxyimino carbonylcompounds in high yields on treatment with butyl nitrite and phenylsilane in the presence of a catalytic amount of N,N′-bis(2-ethoxycarbonyl-3-oxobutylidene)ethylenediaminatocobalt(II)
α,β-不饱和酯、α,β-不饱和酮、α,β-不饱和腈、α,β-不饱和酰胺等多种α,β-不饱和羰基化合物直接转化为相应的α-羟基亚氨基羰基在温和条件下,在催化量的 N,N'-双(2-乙氧基羰基-3-氧代丁二烯)乙二氨基钴 (II) 配合物存在下,用亚硝酸丁酯和苯基硅烷处理高产率的化合物。
Copper-Catalyzed Bis(methoxycarbonyl)carbene Reactions of α,β-Unsaturated Carboxamides
作者:Gökçe Merey、Olcay Anaç
DOI:10.1002/hlca.201000384
日期:2011.6
The [Cu(acac)2]‐catalyzed reactions of α,β‐unsaturated carboxamides with dimethyl diazomalonate yielded dihydrofuran derivatives by a 1,5‐electrocyclic reaction at C(β), and butadiene derivatives by carbene addition reaction at C(α) (Schemes 4 and 5; Table). Phenyl substituents at the N‐atom of the amides seem to be effective on the reaction pathways (Table).
Bifunctional Iminophosphorane-Catalyzed Enantioselective Sulfa-Michael Addition to Unactivated α,β-Unsaturated Amides
作者:Daniel Rozsar、Michele Formica、Ken Yamazaki、Trevor A. Hamlin、Darren J. Dixon
DOI:10.1021/jacs.1c11898
日期:2022.1.19
unactivated α,β-unsaturatedamides is described. Consistently high enantiomeric excesses and yields were obtained over a wide range of alkyl thiol pronucleophiles and electrophiles under mild reaction conditions, enabled by a novel squaramide-based bifunctional iminophosphorane catalyst. Low catalyst loadings (2.0 mol %) were achieved on a decagram scale, demonstrating the scalability of the reaction. Computational
The reaction of N-aryl acrylamides with maleimides in the presence of a ruthenium/rhodium catalyst and Cu(OAc)2·H2O provided succinimide-substituted oxindole derivatives in good to excellent yields. In the reaction, 3,3'-disubstituted oxindoles are produced via a C-H alkylation and intramolecular oxidative cyclization sequence. The proposed mechanism was supported by competition experiments, deuterium