Borrowing Hydrogen: Indirect “Wittig” Olefination for the Formation of C–C Bonds from Alcohols
作者:Phillip J. Black、Michael G. Edwards、Jonathan M. J. Williams
DOI:10.1002/ejoc.200600070
日期:2006.10
development of an indirect three-step domino sequence for the formation of C-Cbondsfromalcohol substrates is described. An iridium-catalysed dehydrogenation of alcohol I affords the intermediate aldehyde 2. The desired C-C bond can then be formed by a facile Wittigolefination, yielding the intermediate alkene 3. In the final step the alkene is hydrogenated to afford the indirectWittig product, the
描述了从醇底物形成 CC 键的间接三步多米诺骨牌序列的成功开发。醇 I 的铱催化脱氢得到中间体醛 2。然后可以通过简单的 Wittig 烯化形成所需的 CC 键,产生中间体烯烃 3。在最后一步中,烯烃被氢化以提供间接的 Wittig 产物,即烷烃 4. 这个过程的关键是借氢的概念;在最初的脱氢步骤中除去的氢气被铱催化剂简单地借用。作为储氢器,催化剂促进 CC 键的形成,然后在最后一步返回借用的氢。在此,我们将详细介绍我们对底物和反应范围以及催化循环的局限性的研究。((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)。
Highly<i>Z</i>-Selective Synthesis of Disubstituted α,β-Unsaturated Cyanides and Amides Using 10-P-5 Wittig Type Reagents
bearing cyanomethyl, acetamide, and N,N-dimethylacetamide groups were examined for Wittig type reactions. All three reacted to give the corresponding olefins. The reaction of the cyanomethyl reagent with aldehydes gave α,β-unsaturated cyanides with high Z-selectivity in the case of aliphatic aldehydes (Z:E=94:6 to 99:1). On the other hand, the reactions of the two amide reagents with aldehydes yielded
The Reaction of Triphenylphosphonium or Triphenylarsonium Salts with Aldehyde: Effect of the Counteranion on their Reactivity
作者:Yung-Son Hon、Chia-Fu Lee
DOI:10.1016/s0040-4020(00)00706-7
日期:2000.9
Some acetonyltriphenylphosphonium, methoxycarbonylmethyltriphenylphosphonium salts and their triphenylarsonium analogues could undergo Wittig reaction with aldehyde in good yields. Their reactivity was counteranion-dependent and was arranged in the following order: p-TsO−, Br−≪CF3CO2−≪ClCH2CO2−
一些丙酮基三苯基phosph盐,甲氧基羰基甲基三苯基phosph盐及其三苯基ar类似物可以与醛进行Wittig反应,收率很高。它们的反应性是抗衡阴离子依赖性的并且被安排在顺序如下:p -TsO - ,溴- «CF 3 CO 2 - «ClCH 2 CO 2 -
Nickel-Catalyzed Reductive Arylation of Redox Active Esters for the Synthesis of α-Aryl Nitriles: Investigation of a Chlorosilane Additive
作者:Nicholas W. M. Michel、Alexis L. Gabbey、Racquel K. Edjoc、Emmanuel Fagbola、Jonathan M. E. Hughes、Louis-Charles Campeau、Sophie A. L. Rousseaux
DOI:10.1021/acs.joc.3c02354
日期:——
iodoarenes for the synthesis of α-aryl nitriles is described. The NHP ester substrate is derived from cyanoacetic acid, which allows for a modular synthesis of substituted α-aryl nitriles, an important scaffold in the pharmaceutical sciences. The reaction exhibits a broad scope, and many functional groups are compatible under the reaction conditions, including complex highly functionalized medicinal agents
The present invention refers to a process for a Rh-catalyzed Anti-Markovnikov hydrocyanation of terminal alkynes which process discloses, for the first time, the highly stereo- and regio-selective hydrocyanation of terminal alkynes to furnish E-configured alkenyl nitriles and the catalyst used in the present process.
本发明涉及一种在 Rh 催化下对末端炔烃进行反马尔科夫尼科夫加氢氰化反应的工艺,该工艺首次公开了对末端炔烃进行高度立体和区域选择性加氢氰化反应以生成 E 构型烯基腈化物的方法以及本工艺中使用的催化剂。