Functionalization of C–H bonds in acetophenone oximes with arylacetic acids and elemental sulfur
作者:Phuc H. Pham、Khang X. Nguyen、Hoai T. B. Pham、Thien T. Tran、Tung T. Nguyen、Nam T. S. Phan
DOI:10.1039/d0ra00808g
日期:——
coupling of acetophenone ketoximes, arylacetic acids, and elemental sulfur in the presence of Li2CO3 base. Functionalities including chloro, bromo, fluoro, trifluoromethyl, and pyridyl groups were compatible with reaction conditions. High yields and excellent regioselectivities were obtained even if meta-substituted ketoxime acetates were used. Ethyl esters of heteroarylacetic acids were competent substrates
在 Li 2 CO 3碱存在下,通过苯乙酮肟、芳基乙酸和元素硫的偶联合成稠合噻吩并[3,2- d ]噻唑。包括氯、溴、氟、三氟甲基和吡啶基在内的官能团与反应条件相容。即使使用间位取代的酮肟乙酸盐,也可以获得高产率和优异的区域选择性。杂芳基乙酸的乙酯是有效的底物,这在文献中非常罕见。我们的方法将提供一个方便的协议,从简单的底物提供多杂环结构。
Rhodium(III)-Catalyzed Synthesis of Pyridines from α,β-Unsaturated Ketoximes and Internal Alkynes
beta-unsaturated oximes and internalalkynes has been developed using [Cp*RhCl2](2)-CsOPiv as the catalyst system. The present transformation is carried out by a redox-neutral sequence of vinylic C-H rhodation, alkyne insertion, and C-N bond formation of the putative vinyl rhodium intermediate with the oxime nitrogen, where the N-Obond of oxime derivatives could work as an internaloxidant to maintain the catalytic
使用 [Cp*RhCl2](2)-CsOPiv 作为催化剂体系开发了一种从 α、β-不饱和肟和内部炔烃合成高度取代的吡啶的方法。目前的转化是通过乙烯基 CH 化、炔插入和 CN 键形成的氧化还原中性序列与肟氮形成推定的乙烯基铑中间体,其中肟衍生物的 NO 键可以作为内部氧化剂来维持催化循环。
Modular Pyridine Synthesis from Oximes and Enals through Synergistic Copper/Iminium Catalysis
作者:Ye Wei、Naohiko Yoshikai
DOI:10.1021/ja312346s
日期:2013.3.13
ketoximes and α,β-unsaturated aldehydes that is synergistically catalyzed by a copper(I) salt and a secondary ammonium salt (or amine). This redox-neutral reaction allows modular synthesis of a variety of substituted pyridines under mild conditions with tolerance of a broad range of functional groups. The reaction is driven by a merger of iminium catalysis and redox activity of the copper catalyst, which
我们在此描述了由铜(I)盐和仲铵盐(或胺)协同催化的 O-乙酰基酮肟和 α,β-不饱和醛的 [3+3] 型缩合反应。这种氧化还原中性反应允许在温和条件下模块化合成各种取代的吡啶,并具有广泛的官能团耐受性。该反应由亚胺催化和铜催化剂的氧化还原活性的结合驱动,最初会还原肟 NO 键以生成亲核铜 (II) 烯酰胺,然后将二氢吡啶中间体氧化为吡啶产物。
Zelinsky, Chemische Berichte, 1887, vol. 20, p. 923