On the Synthesis and Basicity of 1,3-Diaminoisoquinolines
摘要:
A series of 6- and 7-substituted derivatives of 1,3-diaminoisoquinoline were synthesized by the reaction of N,N-diethylarylacetamides with POCl3 and then with N,N-dimethylcyanamide. The products were identified by means of spectroscopic methods and their pK(a) dissociation constants were determined.
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...
A General and Practical Palladium-Catalyzed Direct α-Arylation of Amides with Aryl Halides
作者:Bing Zheng、Tiezheng Jia、Patrick J. Walsh
DOI:10.1002/adsc.201300851
日期:2014.1.13
An efficient system for the direct catalytic intermolecular α‐arylation of acetamide derivatives with aryl bromides and chlorides is presented. The palladium catalyst is supported by Kwong’s indole‐based phosphine ligand and provides monoarylated amides in up to 95% yield. Excellent chemoselectivities (>10:1) in the mono‐ and diarylation with aryl bromides were achieved by careful selection of bases
The direct α‐siladifluoromethylation of lithiumenolates with the Ruppert–Prakash reagent (CF3TMS) is shown to construct the tertiary and quaternary carbon centers. The Ruppert–Prakash reagent, which is versatile for various trifluoromethylation as a trifluoromethyl anion (CF3−) equivalent, can be employed as a siladifluoromethyl cation (TMSCF2+) equivalent by CFbondactivation due to the strong
P450-catalyzed asymmetric cyclopropanation of electron-deficient olefins under aerobic conditions
作者:Hans Renata、Z. Jane Wang、Rebekah Z. Kitto、Frances H. Arnold
DOI:10.1039/c4cy00633j
日期:——
A histidine-ligated variant of P450-BM3 catalyzes cyclopropanation of a variety of electron-deficient olefins under ambient conditions with great selectivity.
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