Rh(<scp>ii</scp>)-catalyzed cycloadditions of 1-tosyl 1,2,3-triazoles with 2H-azirines: switchable reactivity of Rh-azavinylcarbene as [2C]- or aza-[3C]-synthon
作者:Yuanhao Wang、Xiaoqiang Lei、Yefeng Tang
DOI:10.1039/c5cc00268k
日期:——
The Rh(II)-catalyzed formal [3+2] and [3+3] cycloadditions of 1-tosyl 1,2,3-triazoles with 2H-azirines have been developed, which enable the efficient synthesis of polysubstituted 3-aminopyrroles and 1,2-dihydropyrazines, respectively. The reported [3+2] cycloaddition represents the first application of 1-sulfonyl 1,2,3-triazole as a [2C]-component in relevant cycloaddition reactions.
Rh<sup>II</sup>-Catalyzed [3+2] Cycloaddition of 2 <i>H</i>-Azirines with<i>N</i>-Sulfonyl-1,2,3-Triazoles
作者:Yun-Zhou Zhao、Hai-Bin Yang、Xiang-Ying Tang、Min Shi
DOI:10.1002/chem.201406460
日期:2015.2.23
RhII‐catalyzed intermolecular [3+2] cycloaddition of 2 H‐azirines with N‐sulfonyl‐1,2,3‐triazoles is disclosed, in which a series of fully functionalized pyrroles is produced via rhodium azavinyl carbene intermediates. A distinct feature of this reaction is that the azavinyl carbene serves as a [2C] equivalent, instead of as [1 C] or aza‐[3C] synthons, which have been reported previously in cyclopropanations
A simple approach to pyrrolylimidazole derivatives by azirine ring expansion with imidazolium ylides
作者:Alexander F. Khlebnikov、Olesya A. Tomashenko、Liya D. Funt、Mikhail S. Novikov
DOI:10.1039/c4ob00865k
日期:——
A domino reaction of 2H-azirines with 1-alkyl-3-phenacyl-1H-imidazolium bromides in the presence of Et3N provides a facile route to 1-alkyl-3-(1H-pyrrol-3-yl)-1H-imidazol-3-ium bromides. 1-Benzyl derivatives can be reduced to 1-(1H-pyrrol-3-yl)-1H-imidazoles with HCO2NH4 on Pd/C. The action of KOH on pyrrolylimidazolium salts leads to a new type of stable ylide, 3-(1H-imidazol-3-ium-3-yl)-pyrrol-1-ides
Lewis Acid-Catalyzed Diastereoselective Synthesis of Multisubstituted <i>N</i>-Acylaziridine-2-carboxamides from 2<i>H</i>-Azirines via Joullié–Ugi Three-Component Reaction
作者:Anikó Angyal、András Demjén、Edit Wéber、Anita K. Kovács、János Wölfling、László G. Puskás、Iván Kanizsai
DOI:10.1021/acs.joc.7b03189
日期:2018.4.6
A ZnCl2-catalyzed diastereoselective Joullié–Ugi three-component reaction from 2H-azirines, isocyanides, and carboxylic acids was established. The protocol allows the preparation of highly and diversely functionalized N-acylaziridine-2-carboxamide derivatives in up to 82% isolated yields. Moreover, the applicability of N-acylaziridines is demonstrated through a variety of transformations.
Diversity in Gold-Catalyzed Formal Cycloadditions of Ynamides with Azidoalkenes or 2<i>H</i>-Azirines: [3+2] versus [4+3] Cycloadditions
作者:Samir Kundlik Pawar、Rajkumar Lalji Sahani、Rai-Shung Liu
DOI:10.1002/chem.201500694
日期:2015.7.20
Gold‐catalyzed cycloadditions of ynamides with azidoalkenes or 2H‐azirines give [3+2] or [4+3] formal cycloadducts of three classes. Cycloadditions of ynamides with 2H‐azirine species afford pyrrole products with two regioselectivities when the Cβ‐substituted 2H‐azirine is replaced from an alkyl (or hydrogen) with an ester group. For ynamides substituted with an electron‐rich phenyl group, their reactions