Efficient Co(OAc)2-catalyzed aerobic oxidation of EWG-substituted 4-cresols to access 4-hydroxybenzaldehydes
作者:Jian-An Jiang、Jia-Lei Du、Dao-Hua Liao、Zhan-Guo Wang、Ya-Fei Ji
DOI:10.1016/j.tetlet.2013.12.077
日期:2014.2
Co(OAc)2·4H2O/NaOH/O2/ethylene glycol reaction system that enables selective aerobic oxidation of a wide range of substrates covering 2,6-di-EWG-, 2,3,6-tri-EWG-, 2-EWG-, and 2-EWG-6-EDG-substituted 4-cresols into the corresponding 4-hydroxybenzaldehydes. Based on the experimental investigations and well-defined p-benzoquinone methides, a plausible reaction mechanism was proposed. Considering the simplicity of
我们报告了一种高效的无配体Co(OAc)2 ·4H 2 O / NaOH / O 2 /乙二醇反应系统,该系统能够对包括2,6-di-EWG-,2,3在内的多种底物进行选择性好氧氧化,6-tri-EWG-,2-EWG-和2-EWG-6-EDG取代的4-甲酚变成相应的4-羟基苯甲醛。基于实验研究和明确定义的对苯醌甲基化物,提出了合理的反应机理。考虑到程序的简便性和产品的重要性,该方法有望成为相关的苄基C(sp 3)–H官能化化学中的一种有利且实用的工具。
Practical Ligand-Free Copper-Catalysed Short-Chain Alkoxylation of Unactivated Aryl Bromides
作者:Ying Guo、Xue-Min Fan、Min Nie、Hong-Wei Liu、Dao-Hua Liao、Xian-Dao Pan、Ya-Fei Ji
DOI:10.1002/ejoc.201500500
日期:2015.7
developed with special attention focussed on the applicability of the reaction. Sodiumalkoxide is used as the nucleophile, and the correspondingalcohol as the solvent. The reaction requires neither precious metals nor organic ligands. It uses a catalytic system consisting of copper(I) bromide as a catalyst, the corresponding alkyl formate as a noncontaminating cocatalyst, and lithium chloride as an additive