Complementary Stereochemical Outcomes in Proline-Based Self-Regenerations of Stereocenters
摘要:
Stereoselective alkylations of proline-based amino amides are described, where high levels of either a cis or trans configuration can be attained simply by the choice of the aminal group. Isobutryaldehyde-derived aminals provide the cis configuration, while 1-naphthaldehyde-derived aminals engender the complementary trans configuration.
合成由五齿配体H 2 BA R TPP负载的镍配合物[Ni(H 2 BA R TPP)](ClO 4)2(R = Ph表示1或i Pr表示2),并氧化形成Ni III物种具有N3S2配位环境以模仿氧化态的镍超氧化物歧化酶(NiSODox)的活性位点。Ni III物种2 +表现出与 NiSODox相似的g值分别为2.15、2.12和2.02的菱形信号。DFT计算显示2 +具有不成对的电子,主要位于Ni III中心的d轨道,该电子与H 2 BA Pr TPP的轴向吡啶氮的p z轨道强烈重叠。
A Cross-Coupling Approach to Amide Bond Formation from Esters
作者:Taoufik Ben Halima、Jaya Kishore Vandavasi、Mohanad Shkoor、Stephen G. Newman
DOI:10.1021/acscatal.7b00245
日期:2017.3.3
A palladium-catalyzed cross-coupling between aryl esters and anilines is reported, enabling access to diverse amides. The reaction takes place via activation of the C–O bond by oxidative addition with a Pd–NHC complex, which enables the use of relatively non-nucleophilic anilines that otherwise require stoichiometric activation with strong bases in order to react. High yields of aromatic, aliphatic
Oxazoline-Substituted Prolinamide-Based Organocatalysts for the Direct Intermolecular Aldol Reaction between Cyclohexanone and Aromatic Aldehydes
作者:Simon Doherty、Julian G. Knight、Amy McRae、Ross W. Harrington、William Clegg
DOI:10.1002/ejoc.200700922
日期:2008.4
Oxazoline-substituted prolinamides catalyse the direct asymmetric aldol reaction between cyclohexanone and a range of aldehydes to give excellent conversions and enantioselectivities up to 84 % under optimum conditions. Reactions were highly substrate-specific with electron-deficient aldehydes giving the highest yields and ee values. The absolute configuration of the 4-chlorobenzaldehyde-derived product
Clickable coupling of carboxylic acids and amines at room temperature mediated by SO<sub>2</sub>F<sub>2</sub>: a significant breakthrough for the construction of amides and peptide linkages
作者:Shi-Meng Wang、Chuang Zhao、Xu Zhang、Hua-Li Qin
DOI:10.1039/c9ob00699k
日期:——
carboxylic acids with amines was developed for the synthesis of a broad scope of amides in a simple, mild, highly efficient, robust and practical manner (>110 examples, >90% yields in most cases). The direct click reactions of acids and amines on a gram scale are also demonstrated using an extremely easy work-up and purification process of washing with 1 M aqueous HCl to provide the desired amides in
Amine Activation:<i>N</i>-Arylamino Acid Amide Synthesis from Isothioureas and Amino Acids
作者:Yan-Ping Zhu、Pieter Mampuys、Sergey Sergeyev、Steven Ballet、Bert U. W. Maes
DOI:10.1002/adsc.201700134
日期:2017.7.17
functional group compatibility, with respect to side chain functionality of the amino acid (e. g. aliphatic and aromatic OH, (hetero)aromatic NH, amide NH, thioether), and the chiral amino acids do not undergo epimerization. The mechanism of the new amidesynthesis has been studied.
Cross-Coupling Reactions of Aryl Halides with Amines, Phenols, and Thiols Catalyzed by an N,N′-Dioxide-Copper(I) Catalytic System
作者:Haitao Yang、Chao Xi、Zhiwei Miao、Ruyu Chen
DOI:10.1002/ejoc.201100274
日期:2011.6
reactions of various N, O, and S nucleophilic reagents with aryl halides have been successfully carried out under mild conditions by using a novel chiral N,N′-dioxide–copper(I) catalytic system as the catalyst. This versatile and efficient catalyst system has been demonstrated to facilitate the cross-coupling reactions of aryl halides with amines,phenols, and thiols to afford the corresponding desired
通过使用新型手性 N,N'-二氧化物-铜 (I) 催化体系作为催化剂,各种 N、O 和 S 亲核试剂与芳基卤化物的偶联反应已在温和条件下成功进行。这种多功能且高效的催化剂体系已被证明可促进芳基卤化物与胺、酚和硫醇的交叉偶联反应,从而以良好至极好的收率提供相应的所需产物。