Palladium-Catalyzed α-Arylation of Esters and Amides under More Neutral Conditions
作者:Takuo Hama、Xiaoxiang Liu、Darcy A. Culkin、John F. Hartwig
DOI:10.1021/ja036792p
日期:2003.9.1
aryl halides with alkalimetal enolates are reported. The first procedure rests upon the development of catalysts bearing the hindered pentaphenylferrocenyl di-tert-butylphosphine (Q-phos) and the highly reactive dimeric Pd(I) complex P(t-Bu)3]PdBr}2. By this procedure, zinc enolates prepared from α-bromo esters and amides react with aryl halides to form α-aryl esters and amides in high yields under
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...
Amination of phenylketenes. Substituent effect on amine-catalyzed tautomerization of amide enol
reaction of substituted phenylketenes with diethylamine in acetonitrile were suggested to be the amideenols rather than the zwitterions on the basis of the theoretical calculations. A single broad band at 1674 cm−1 observed for reaction with the primary amines was attributed to overlap of two bands of the intermediate (amideenol) and the final product (amide). The substituenteffect for the second‐order