Thionium ion promoted Michael acceptor: a sequence of Pummerer/Michael reactions for the stereoselective synthesis of 5-(1-(arylthio)vinyl)-oxazolines
摘要:
The synthesis of polysubstituted oxazolines is of great interest due to the synthetic and pharmaceutical importance. We developed a sequence of Pummerer/Michael reactions for the stereoselective synthesis of 5-(1-(arylthio)vinyl)-oxazolines. (C) 2014 Elsevier Ltd. All rights reserved.
An Efficient FeCl3-Catalyzed Condensation of Thiols with 1,3-Dicarbonyl Compounds under Solvent-Free Conditions
作者:Krishna Singh、Kumkum Kumari
DOI:10.1055/s-0033-1340054
日期:——
A practical and environmentally friendly method has been developed for the synthesis of thiol-substituted cyclohex-2-enones using a FeCl 3 -catalyzed condensation of cyclic 1,3-dicarbonylcompounds and aromatic/aliphatic thiols under solvent-free conditions at ambient temperature.
synthesis of aryl alkyl ethers has been described. DMSO is employed as the mild terminal oxidant. This novel methodology offers a metal‐free reaction condition, operational simplicity and broad substrate scope to afford valuable products from inexpensive reagents. Various meta‐substituted aromatic ethers which are hardly synthesized from the reported methods requiring meta‐substituted phenols, are efficiently
The manuscript describes a novel and efficient transition-metal-free approach to substituted phenols from simple and readily available cyclohexenones and cyclohexanones. Dimethyl sulfoxide (DMSO), the simple and common organic reagent, was...
cobaloxime to produce olefins and H2. This operationally simple method enables direct dehydrogenation of readily available chemical feedstocks to diversely functionalized olefins. For example, we demonstrate, for the first time, the oxidant-free desaturation of thioethers and amides to alkenyl sulfides and enamides, respectively. Moreover, the system’s exceptional siteselectivity and functional group
脂肪族催化脱氢 (CDA) 在有机合成中的价值在很大程度上仍未得到充分探索。已知的均相 CDA 系统通常需要使用牺牲氢受体(或氧化剂)、贵金属催化剂和苛刻的反应条件,因此将大多数现有方法限制为非或低官能化烷烃的脱氢。在这里,我们描述了一种可见光驱动的双催化剂系统,该系统由廉价的有机光氧化还原和贱金属催化剂组成,用于室温、无受体 CDA (Al-CDA)。该过程由光激发的 2-氯蒽醌引发,涉及脂肪族的 H 原子转移 (HAT) 形成烷基自由基,然后与钴肟反应生成烯烃和 H 2. 这种操作简单的方法能够将容易获得的化学原料直接脱氢成多种官能化的烯烃。例如,我们首次证明了硫醚和酰胺在无氧化剂条件下分别脱饱和为烯基硫醚和烯酰胺。此外,14 种生物相关分子和药物成分的后期脱氢和合成说明了该系统卓越的位点选择性和官能团耐受性。机理研究揭示了双重 HAT 过程,并提供了对反应性和位点选择性起源的见解。
Thionium ion promoted Michael acceptor: a sequence of Pummerer/Michael reactions for the stereoselective synthesis of 5-(1-(arylthio)vinyl)-oxazolines
作者:Shimin Xu、Qianyun Zhang、Hongwei Zhou
DOI:10.1016/j.tetlet.2013.12.112
日期:2014.2
The synthesis of polysubstituted oxazolines is of great interest due to the synthetic and pharmaceutical importance. We developed a sequence of Pummerer/Michael reactions for the stereoselective synthesis of 5-(1-(arylthio)vinyl)-oxazolines. (C) 2014 Elsevier Ltd. All rights reserved.