使用廉价且定义明确的 (6-OH-bpy)NiCl 2催化剂通过NN键活化实现偶氮芳烃与苯甲醇的化学发散(脱)氢偶联。该协议强调了通过提供取代亚胺和胺的借氢策略构建 C-N 键。在串联氢化/脱氢过程中,一系列偶氮化合物与各种取代的苯甲醇偶联。镍催化剂连同 K 2 CO 3或 KO tBu 碱控制亚胺和胺形成的选择性。一项初步的机理研究确定了金属-配体合作 (MLC) 的关键作用,包括不同的自由基途径。
Manganese(I)-Catalyzed Transfer Hydrogenation and Acceptorless Dehydrogenative Condensation: Promotional Influence of the Uncoordinated N-Heterocycle
作者:Chong Zhang、Bowen Hu、Dafa Chen、Haiping Xia
DOI:10.1021/acs.organomet.9b00475
日期:2019.8.26
showed the highest activity. The reactions proceeded well with 0.5 mol % of catalyst loading and 20 mol % of t-BuOK at 85 °C for 24 h. Furthermore, 3 was also used as a catalyst for the synthesis of primary alcohols via transfer hydrogenation of aldehydes and the synthesis of 1,2-disubstituted benzimidazoles and quinolines via acceptorless dehydrogenative condensations.
四种二齿锰(I)配合物[(C 5 H 4 N-C 5 H 3 N-OH)Mn(CO)3 Br](1),[(C 9 H 6 N-C 5 H 3 N-OH)Mn(CO )3 Br](2),[(C 8 H 5 N 2 -C 5 H 3 N-OH)Mn(CO)3 Br](3)和[(C 8 H 5 N 2 -C 5 H 3 N-OCH 3)Mn(CO)3Br](4)被合成。测试了这些配合物作为酮转移氢化的催化剂,其中3种显示出最高的活性。在85℃下,在0.5mol%的催化剂负载量和20mol%的t- BuOK下,反应进行得很好,持续了24小时。此外,3还用作催化剂,用于通过醛的转移氢化合成伯醇,以及通过无受体的脱氢缩合反应合成1,2-二取代的苯并咪唑和喹啉。
A CONVENIENT METHOD FOR THE DIRECT PREPARATION OF KETONES FROM 2-(6-(2-METHOXYETHYL)PYRIDYL)CARBOXYLATES AND ALKYL IODIDES BY USE OF ZINC DUST AND A CATALYTIC AMOUNT OF NICKEL DICHLORIDE
作者:Makoto Onaka、Yoshio Matsuoka、Teruaki Mukaiyama
DOI:10.1246/cl.1981.531
日期:1981.4.5
Treatment of 2-(6-(2-methoxyethyl)pyridyl) carboxylates with alkyl iodides in the presence of zinc dust and a catalytic amount of NiCl2 in DMF at 50 °C affords unsymmetrical ketones in good yields by a one-pot procedure.
在锌粉和催化量的 NiCl2 的 DMF 存在下,在 50 °C 下用烷基碘处理 2-(6-(2-甲氧基乙基)吡啶基)羧酸酯,通过一锅法以良好的收率提供不对称酮。
Dehydrogenative Oxidation of Alcohols in Aqueous Media Using Water-Soluble and Reusable Cp*Ir Catalysts Bearing a Functional Bipyridine Ligand
A new catalytic system for the dehydrogenative oxidation of alcohols using a water-soluble Cp*Ir complexbearing a bipyridine-based functionalligand as catalyst has been developed. With this catalytic system, a variety of primary and secondary alcohols have been efficiently converted to aldehydes and ketones, respectively, in aqueousmedia without using any oxidant. Reuse of the catalyst by a very
A Metathesis-Based Approach to the Synthesis of 2-Pyridones and Pyridines
作者:Timothy J. Donohoe、Lisa P. Fishlock、Panayiotis A. Procopiou
DOI:10.1021/ol702684d
日期:2008.1.1
intermediates, which are in the correct oxidation state to undergo a base-induced elimination to reveal the aromatic 2-pyridone. This mild and novel approach to six-memberedheteroaromatic compounds then provides access to a wide variety of substituted pyridines in excellent overall yield.
Primary and secondaryalcohols are acylated under mild conditions by the use of 2,2′-bipyridyl-6-yl carboxylates and cesium fluoride. Furthermore, the reaction is successfully applied to selectiveacylation of a primary carbinol group of diols containing primary and secondary carbinol groups or exclusive O-acylation of aromatic amino alcohols.