[reaction: see text] Reaction of carbamoyl chlorides with cyano-Gilman cuprates affords tertiary amides in good to excellent yields. The reaction is general due to the possibility of using reagents made either from organolithium or from Grignard compounds. The characterization of the main side products allowed for the suggestion of a possible mechanism.
Palladium-Catalyzed Intermolecular α-Arylation of Zinc Amide Enolates under Mild Conditions
作者:Takuo Hama、Darcy A. Culkin、John F. Hartwig
DOI:10.1021/ja056076i
日期:2006.4.1
The intermolecular α-arylation and vinylation of amides by palladium-catalyzedcoupling of aryl bromides and vinyl bromides with zinc enolates of amides is reported. Reactions of three different types of zinc enolates have been developed. The reactions of aryl halides occur in high yields with isolated Reformatsky reagents generated from α-bromo amides, with Reformatsky reagents generated in situ from
报道了通过芳基溴化物和乙烯基溴化物与酰胺的烯醇锌的钯催化偶联,酰胺的分子间α-芳基化和乙烯基化。已经开发了三种不同类型的烯醇化锌的反应。芳基卤化物与由 α-溴酰胺产生的分离的 Reformatsky 试剂、由 α-溴酰胺原位产生的 Reformatsky 试剂以及通过用氯化锌淬灭酰胺的烯醇锂而产生的烯醇锌以高产率发生反应。这种使用锌烯醇化物代替碱金属烯醇化物极大地扩展了酰胺芳基化的范围。该反应在室温或 70 °C 下与含有氰基、硝基、酯、酮、氟、羟基或氨基官能团的溴芳烃以及溴吡啶发生反应。此外,该反应已开发与吗啉酰胺,其产物是酮和醛的前体。酰胺的烯醇锌的芳基化是用带有受阻五苯的催化剂进行的...
Hydroxamic Acids as Chemoselective (<i>ortho</i>
-Amino)arylation Reagents via Sigmatropic Rearrangement
The use of readily available hydroxamic acids as reagents for the chemoselective (ortho‐amino)arylation of amides is described. This reaction proceeds under metal‐free, mild conditions, displays a very broad scope, and constitutes a direct approach for the metal‐free attachment of aniline residues to carbonyl derivatives.
Nickel-catalyzed cross-coupling of unactivated alkyl halides and tosylate carrying a functional group with alkyl and phenyl Grignard reagents
作者:Surya Prakash Singh、Jun Terao、Nobuaki Kambe
DOI:10.1016/j.tetlet.2009.07.094
日期:2009.10
primary and secondaryalkylGrignardreagents undergo cross-coupling with alkyl bromides, iodide, and tosylate carrying a functional group such as amide, ester, and ketone at 0 °C in THF. The present procedure provides a simple, convenient, and practical method for construction of carbon chains in the presence of various functional groups. PhMgBr also gave the corresponding coupling product in a moderate
General and Efficient α-Oxygenation of Carbonyl Compounds by TEMPO Induced by Single-Electron-Transfer Oxidation of Their Enolates
作者:Emanuela Dinca、Philip Hartmann、Jakub Smrček、Ina Dix、Peter G. Jones、Ullrich Jahn
DOI:10.1002/ejoc.201200736
日期:2012.8
for the synthesis of protected α-oxygenated carbonylcompounds is reported. It is based on the single-electron-transfer oxidation of easily generated enolates to the corresponding α-carbonyl radicals. Coupling with the stable free radical TEMPO provides α-(piperidinyloxy) ketones, esters, amides, acids or nitriles in moderate-to-excellent yields. Enolate aggregates influence the outcome of the oxygenation