Cycloadducts of nitrones with isocyanates; 1,2,4- or 1,3,4-oxadiazolidinones?
作者:Anthony M. T. Bell、Jonathan Bridges、Richard Cross、Christopher P. Falshaw、Brian F. Taylor、Giles A. Taylor、Ian C. Whittaker、Michael J. Begley
DOI:10.1039/p19870002593
日期:——
The adducts formed between various aryl-substituted nitrones and aryl isocyanates have been shown, using 15N n.m.r. spectroscopy and X-ray crystallography, to be substituted 1,2,4-oxadiazolidinones and not the previously reported 1,3,4-oxadiazolinones.
使用15 N nmr光谱法和X射线晶体学显示,各种芳基取代的硝酮与芳基异氰酸酯之间形成的加合物被取代的1,2,4-恶二唑烷酮,而不是先前报道的1,3,4-恶二唑啉酮。
Synthesis of 1,2,4-oxadiazolidines <i>via</i> [3+2] cycloaddition of nitrones with carbodiimides
An efficient [3+2] cycloaddition of nitrones and carbodiimides has been developed. This 1,3-dipolar cycloaddition features high regioselectivity, mild and metal-free conditions, excellent functional group compatibility, and a broad substrate scope. The X-ray structures of two regio-isomers confirmed the regioselectivity of this transformation.
Diversity-oriented synthesis of 1,2,3,5-tetrahydrobenzo[e][1,2,4]oxadiazepines and 2,3-dihydro-1H-benzo[e][1,2,4]triazepines by base-induced [4 + 3] annulation reactions
作者:Wuyan Long、Shuangqun Chen、Xiaohong Zhang、Ling Fang、Zhiyong Wang
DOI:10.1016/j.tet.2018.09.004
日期:2018.10
The base-induced formal [4 + 3] annulation reactions of N-(ortho-chloromethyl)aryl amides with nitrones or hydrazonoyl chlorides have been reported. When nitrones are used as the 1,3-dipole, the corresponding reaction afforded a series of 1,2,3,5-tetrahydrobenzo[e][1,2,4]oxadiazepine derivatives. Highly functionalized 2,3-dihydro-1H-benzo[e][1,2,4]triazepine derivatives were also synthesized via an
已经报道了碱诱导的N-(邻氯甲基)芳基酰胺与硝酮或酰肼基氯化物的正式[4 + 3]环化反应。当将硝酮用作1,3-偶极时,相应的反应得到一系列1,2,3,5-四氢苯并[ e ] [1,2,4]恶二氮杂衍生物。还通过N-(邻-氯甲基)芳基酰胺和酰基之间空前的串联氮杂-迈克尔加成/重排芳构化反应合成了高度官能化的2,3-二氢-1 H-苯并[ e ] [1,2,4]三氮杂卓衍生物氯化物。
Copper(I)-Catalyzed Asymmetric 1,3-Dipolar [3+4] Cycloaddition of Nitrones with Azoalkenes
作者:Liang Wei、Lu Yao、Zuo-Fei Wang、Hua Li、Hai-Yan Tao、Chun-Jiang Wang
DOI:10.1002/adsc.201600457
日期:2016.12.7
The first copper(I)‐catalyzed asymmetric1,3‐dipolar [3+4] cycloaddition of nitrones with azoalkenes has been developed, affording a variety of biologically important 1,2,4,5‐oxatriazepane derivatives in good yields with exclusive regioselectivities and excellent enantioselectivities.