Nitrone Cycloadditions to 1,2-Diphenylcyclopropenes and Subsequent Transformations of the Isoxazolidine Cycloadducts
作者:Vyacheslav V. Diev、Oksana N. Stetsenko、Tran Q. Tung、Jürgen Kopf、Rafael R. Kostikov、Alexander P. Molchanov
DOI:10.1021/jo702379d
日期:2008.3.1
occurs with the formation of expected “normal” cycloadducts (with N-methylnitrones) and products of their subsequent transformations. Among them are corresponding α-acetophenyl aziridines and tetra (or penta) -arylpyrroles. Aziridines and the normal cycloadducts can be also thermally converted to such arylpyrroles with moderate to good yields. Substitution at the C3 position of cyclopropenes by an electron
1,3-Dipolar Cycloaddition Reactionsof Nitrones to Prop-1-ene-1,3-sultone
作者:Lun-Zu Liu、Li Tian、Guo-Yan Xu、Yong Ye
DOI:10.1055/s-2003-40201
日期:——
The reaction of prop-1-ene-1,3-sultone (1) with a variety of nitrones 2 afforded novel [3+2] cycloaddition products 3, 4, and 5 in good yield. Excellent regio- and stereoselectivity were achieved in the cycloaddition reaction with phenylnitrones.
Cooperative Silver- and Base-Catalyzed Diastereoselective Cycloaddition of Nitrones with Methylene Isocyanides: Access to 2-Imidazolinones
作者:Yan Chen、Yijing Wu、Andrey Shatskiy、Yuhe Kan、Markus D. Kärkäs、Jian-Quan Liu、Xiang-Shan Wang
DOI:10.1002/ejoc.202000437
日期:2020.6.23
A protocol involving cooperative silver‐ and base‐catalyzed diastereoselective cycloaddition of nitrones with isocyanides is described, delivering several valuable 2‐imidazolinones derivatives as single diastereomers. A plausible reaction mechanism is rationalized by DFT calculations. DBU plays dual roles in the developed reaction, acting as both the base and ligand.
Enantioselective 1,3-Dipolar Cycloaddition Reaction of Nitrones with α,β-Unsaturated Aldehydes Catalyzed by Cationic 3-Oxobutylideneaminatocobalt(III) Complexes
complex, the enantioselective1,3-dipolarcycloaddition reaction of various nitrones with α,β-unsaturatedaldehydes afforded the corresponding isoxazolidines in high yields and with high enantioselectivities. The absolute configuration of the optically active products was determined by X-ray analysis. Reasonable explanations for the enantioselection in the present 1,3-dipolarcycloaddition reaction catalyzed
硝酮与α,β-不饱和醛的对映选择性1,3-偶极环加成反应是使用3-氧代丁基亚氨基钴配合物催化剂实现的。筛选了各种钴 (II) 和钴 (III) 配合物,发现阳离子钴 (III) 配合物与六氟锑酸盐对催化对映选择性 1,3-偶极环加成反应最有效。在六氟锑酸钴 (III) 络合物的存在下,各种硝酮与 α,β-不饱和醛的对映选择性 1,3-偶极环加成反应以高产率和高对映选择性提供相应的异恶唑烷。旋光产物的绝对构型通过 X 射线分析确定。对当前1中对映选择的合理解释,
Enantioselective 1,3-Dipolar Cycloaddition of Nitrones Catalyzed by Optically Active Cationic Cobalt(III) Complexes
cobalt(III) complexes were employed as efficient Lewis acid catalysts for the enantioselective1,3-dipolarcycloaddition reaction of alpha,beta-unsaturated aldehydes with nitrones. Excellent endo selectivities and high enantioselectivities were achieved in the cycloaddition reaction of 1-cyclopentene-1-carbaldehyde and the nitrones derived from 2-halobenzaldehyde.