Simple aromatic substituents in the substrate molecule, including pyrimidine, pyridine, and benzene rings, directly facilitated the intramolecular cycloaddition of azomethine ylide to alkene. All of these aromatic substituents aided the formation of azomethine ylides, which then underwent highly diastereospecific sequential cycloaddition. It was shown that both the presence of an electron-deficient
Copper-catalyzed radical cascade cyclization of 2-(allyloxy)arylaldehydes towards chroman-4-one derivatives
作者:Wenbin Guo、Linlin Gui、Xin Chen、Zhijun Dai、Liping Wang、Xiaoji Wang
DOI:10.1016/j.tetlet.2021.153605
日期:2022.3
A copper catalyzed difluoroacetylation of 2-(allyloxy)arylaldehydes was disclosed. In the present transformation, various 2-(allyloxy)arylaldehydes and difluoro reagents were performed smoothly, and a serises of chroman-4-one derivatives were generated in moderate to good yields viaradicalcascade cyclization. This protocol could promise a practical and efficient synthetic method for pharmaceutically
Expedient synthesis of tetrahydroquinoline-3-spirohydantoin derivatives via the Lewis acid-catalyzed tert-amino effect reaction
作者:John F. Briones、Gregory S. Basarab
DOI:10.1039/c6cc03600g
日期:——
Magnesium triflate was found to effectively catalyze the tert-amino effect reaction (T-reaction) involving ethyl 3-(2-(dialkylamino)-phenyl)-2-nitroacrylates leading to tetrahydroquinoline nitroester derivatives. These compounds can be readily transformed to the corresponding valuable spirohydantoin derivatives.
Visible-light-induced transition metal and photosensitizer free decarbonylative addition of amino-arylaldehydes to ketones
作者:Yi Wang、Yatao Lang、Chao-Jun Li、Huiying Zeng
DOI:10.1039/d1sc06278f
日期:——
decarbonylative-coupling reaction is generally promoted by transition metals (via organometallic complexes) or peroxides (via radical intermediates), often at high temperatures to facilitate the CO release. Herein, a visible-light-induced, transition metal and external photosensitizer free decarbonylative addition of benzaldehydes to ketones/aldehydes at room temperature is reported. Tertiary/secondary alcohols were
脱羰基偶联反应通常由过渡金属(通过有机金属络合物)或过氧化物(通过自由基中间体),通常在高温下以促进 CO 释放。本文报道了一种在室温下由可见光诱导的、过渡金属和无外部光敏剂的苯甲醛与酮/醛脱羰基加成反应。通过在温和条件下使用 CsF,可以以中等至优异的产率获得叔/仲醇。详细的机理研究表明,该反应通过醛的光激发-脱羰生成芳香族阴离子,然后将其添加到酮/醛中。通过密度泛函理论(DFT)计算验证了反应机理。
A Cascade of Acid-Promoted C–O Bond Cleavage and Redox Reactions: From Oxa-Bridged Benzazepines to Benzazepinones
作者:Yuewei Zhang、Fengzhi Yang、Lianyou Zheng、Qun Dang、Xu Bai
DOI:10.1021/ol502971e
日期:2014.12.5
A sequence of C–O bond cleavage and redox reactions in oxa-bridged azepines was realized under acid promoted conditions. This protocol provides an atom-economical and straightforward approach to access benzo[b]azepin-5(2H)-ones in high yields. The formal synthesis of tolvaptan was achieved by exploiting this new transformation.
在酸促进的条件下,在氧杂桥联的ze庚烷中实现了一系列的C–O键断裂和氧化还原反应。该协议提供了一种原子经济且直接的方法,可以高产率获得苯并[ b ] azepin-5(2 H)-。托伐普坦的正式合成是通过利用这一新的转化而实现的。