Unexpected Aldehyde-Catalyzed Reaction of Imidazole N-Oxides with Ethyl Cyanoacetate
作者:Anton V. Kutasevich、Anna S. Efimova、Marina N. Sizonenko、Valery P. Perevalov、Ludmila G. Kuz’mina、Vitaly S. Mityanov
DOI:10.1055/s-0039-1691527
日期:2020.1
The reaction of 2-unsubstituted imidazole N-oxides with ethyl cyanoacetate and aromatic aldehydes leads to the formation of ethyl 2-cyano-2-(1,3-dihydro-2H-imidazole-2-ylidene)acetates. The reaction proceeds through an initial [3+2] cycloaddition, followed by cleavage of the cycloadduct and regeneration of the aldehyde, which essentially plays a catalytic role.
New Synthetic Approach for the Preparation of Imidazole<i>N</i>
<sup>3</sup>-Oxide
作者:Hugo Cerecetto、Mercedes González、Alejandra Gerpe、Yolanda Fernández Sainz、Oscar E. Piro、Eduardo E. Castellano
DOI:10.1055/s-2004-831212
日期:——
A new synthetic procedure of 1-alkyl(aryl)-1H-4-methylimidazole N 3 -oxide derivatives by cyclocondensation of α-amine-oximes and orthoesters was studied. Low yields in the cyclization process were the result of predominant Z-stereoisomer around the oxime moiety of α-amineoxime reactants. Different attempts to improve these yields were assayed, mild conditions being those that produce the best results
A new facile method for the synthesis of 3-imidazolylpropionic acid N-oxides
作者:Anton V. Kutasevich、Valery P. Perevalov、Vitaly S. Mityanov、Boris V. Lichitsky、Andrey N. Komogortsev、Mikhail M. Krayushkin、Tatyana Yu. Koldaeva、Vladimir S. Miroshnikov
DOI:10.1007/s10593-019-02431-7
日期:2019.2
A facile and efficient method for the preparation of 3-imidazolylpropionic acid N-oxides has been developed. It involves condensation of 2-unsubstituted imidazole N-oxide with an aldehyde and Meldrum's acid followed by hydrolysis and decarboxylation of the corresponding adduct. This method tolerates a broad variation in the structure of starting aldehydes as well as N-oxides.
Synthesis of highly functional imidazole derivatives via assembly of 2-unsubstituted imidazole N-oxides with CH-acids and arylglyoxals
作者:Valery P. Perevalov、Vitaly S. Mityanov、Boris V. Lichitsky、Andrey N. Komogortsev、Ludmila G. Kuz’mina、Tatyana Yu. Koldaeva、Vladimir S. Miroshnikov、Anton V. Kutasevich
DOI:10.1016/j.tet.2020.130947
日期:2020.2
A novel and convenient method for the synthesis of a wide range of polyfunctional imidazolederivatives based on the three-component condensation of imidazole N-oxides with CH-acids and arylglyoxals has been developed. This reaction proceeds smoothly in moderate-to-good yields with a wide range of starting materials.