Highly Efficient Synthesis of Allenes from Trimethylaluminum Reagent and Propargyl Acetates Mediated by a Palladium Catalyst
作者:Qing-Han Li、Jung-Yuan Jeng、Han-Mou Gau
DOI:10.1002/ejoc.201403008
日期:2014.12
A series of propargylacetates were prepared and used as propargyl electrophiles for coupling reactions with trimethylaluminum. The simple catalytic system of palladium(II) acetate (1 mol-%) and tri(o-tolyl)phosphine (2 mol-%) worked efficiently for a wide variety of aromatic and aliphatic propargylacetates, producing the substituted allenes in good to excellent yields of up to 94 % in tetrahydrofuran
制备了一系列乙酸炔丙酯并将其用作炔丙基亲电试剂与三甲基铝进行偶联反应。乙酸钯 (II) (1 mol-%) 和三(邻甲苯基)膦(2 mol-%)的简单催化体系对多种芳香族和脂肪族乙酸炔丙酯有效地工作,产生了良好的取代丙二烯在四氢呋喃中的产率高达 94%。该过程简单易行,为合成取代的丙二烯衍生物提供了一种有效的方法。根据实验结果,提出了一种可能的催化循环。
Synthesis of multi-substituted allenes from organoalane reagents and propargyl esters by using a nickel catalyst
作者:Xue Bei Shao、Zhen Zhang、Qing Han Li、Zhi Gang Zhao
DOI:10.1039/c8ob00781k
日期:——
A highly efficient and simple route for the synthesis of multi-substituted allenes has been developed by a nickel catalyzed SN2′ substitution reaction of propargyl esters with organic aluminium reagents under mild conditions, which gave the corresponding multi-substituted allenes in good to excellent yields (up to 92%) and high selectivities (up to 99%) at 60 °C for 6 h in THF. Aryls bearing electron-donating
在温和的条件下,通过炔丙基酯与有机铝试剂的镍催化的S N 2'取代反应,开发了一种高效且简单的合成多取代的烯的方法,得到了相应的优等的多取代的烯。在THF中在60°C下反应6小时可得到高产率(最高92%)和高选择性(最高99%)。炔丙基酯中带有给电子或吸电子基团的芳基收率高。另外,带有噻吩基或吡啶基的多取代的亚丙基以95-97%的选择性获得,分离产率为72-83%。此外,S N2'取代反应也与炔丙基碳酸酯化合物有效地起作用。根据实验结果,提出了可能的催化循环。
Pd-Catalyzed Intermolecular Carbonylative Dearomatization of Arylamines with Propargylic Acetates for Synthesis of Bridged Polycyclic Lactams
作者:Qi Xue、Ren Wang、Wen-Yu Zhang、Fang-Fang Shen、Yang Li、Qing Sun、Jin-Heng Li
DOI:10.1021/acs.orglett.3c01344
日期:2023.6.16
A new palladium-catalyzed multicomponent dearomatization of arylamines with CO and propargylic acetates for the synthesis of bridged polycyclic lactams is described. This method allows double annulation at the ipso and para positions of the amino group to form four new bonds, three C–C bonds and one C–N bond. DFT calculations and experimental studies indicate that the efficient formation of the allenecarboxanilide
描述了一种新的钯催化芳基胺与 CO 和炔丙基乙酸酯的多组分脱芳构化反应,用于合成桥接多环内酰胺。该方法允许在氨基的ipso和para位置双环化以形成四个新键,三个 C-C 键和一个 C-N 键。DFT计算和实验研究表明,高效形成丙二烯甲酰苯胺中间体是实现脱芳烃转化的关键步骤。