已实现了钯催化的三组分羰基化反应,该反应可从酰氯和NaN 3合成3 H -1,2,4-三唑-3-酮。该反应大概通过级联羰基化,酰基叠氮化物形成,Curtius重排和分子内亲核加成序列进行。以中等至优异的产率构建了各种结构多样的3 H -1,2,4-三唑-3-酮。1,2,3,5-三甲酸三苯酯(TFBen)被用作固体和方便的一氧化碳替代物。
An operationally simple and convenient synthesis method toward a series of diverse spiro[4.4]thiadiazole derivatives via double [3 + 2] 1,3-dipolarcycloaddition of nitrilimines generated in situ from hydrazonyl chlorides with carbon disulfide has been achieved undermild reaction conditions.
1,3-Dipolar Cycloaddition of Nitrile Imine with Carbon Dioxide: Access to 1,3,4-Oxadiazole-2(3<i>H</i>)-ones
作者:Chun-Xiao Guo、Wen-Zhen Zhang、Ning Zhang、Xiao-Bing Lu
DOI:10.1021/acs.joc.7b00963
日期:2017.7.21
Efficient synthesis of 1,3,4-oxadiazole-2(3H)-one was achieved by CsF/18-crown-6 mediated 1,3-dipolar cycloaddition of nitrile imine and 2.0 MPa of CO2. CsF/18-crown-6 played a key role in enhancing the reactivity of CO2 as a 1,3-dipolarophile. The practical utility of this transition-metal-free approach to 1,3,4-oxadiazole-2(3H)-one is highlighted by the convenient synthesis of a commercial herbicide
cycloaddition of nitrile imines with 3-alkenyl-oxindoles was catalyzed by a new chiral Mg(ClO4)2 complex of an N,N′-dioxide ligand. The reaction is so far the sole catalytic synthesis of spiro-pyrazoline-oxindole derivatives. A wide variety of substrates were explored to obtain good yields (up to 98%) and excellent enantioselectivities (up to 99%). This cycloaddition expands the scope of propargyl anion type 1
Regioselective [3 + 2]-annulation of hydrazonyl chlorides with 1,3-dicarbonyl compounds for assembling of polysubstituted pyrazoles
作者:Kun Liu、Xinye Shang、Yuyu Cheng、Xiaoyong Chang、Pengfei Li、Wenjun Li
DOI:10.1039/c8ob02352b
日期:——
The facile approach to polysubstituted pyrazoles from hydrazonyl chlorides and 1,3-dicarbonyl compounds has been developed. Hydrazonyl chlorides reacted with N-phenyl-3-oxobutanamides smoothly to afford a series of polysubstituted pyrazoles in 67–98% yields via the [3 + 2]-cycloaddition.