84679-62-9Relevant academic research and scientific papers
Synthesis of exo-Imidazolidin-2-one Dienes, Their Isomerization, and Selectivity in Diels-Alder Cycloadditions
Espinoza-Hicks, Carlos,Montoya, Pablo,Bautista, Rafael,Jiménez-Vázquez, Hugo A.,Rodríguez-Valdez, Luz M.,Camacho-Dávila, Alejandro A.,Cossío, Fernando P.,Delgado, Francisco,Tamariz, Joaquín
, p. 5347 - 5364 (2018/05/28)
An efficient and alternative synthesis of exo-imidazolidin-2-one dienes is described. A condensation reaction was carried out with bis-imino derivatives, diacetyl, and triphosgene, affording symmetrically N,N-disubstituted dienes. The use of alkyl methyl
Synthesis and Diels - Alder cycloadditions of exo-imidazolidin-2-one dienes
Bautista, Rafael,Bernal, Pablo,Herrera, Rafael,Santoyo, Blanca M.,Lazcano-Seres, J. Miguel,Delgado, Francisco,Tamariz, Joaquin
experimental part, p. 7901 - 7911 (2011/11/29)
(Figure presented) An efficient and versatile synthesis of novel exo-imidazolidin-2-one dienes is described. This involves the base-assisted condensation/cyclization cascade reaction of the monoimino derivatives of diacetyl with a series of isocyanates. This methodology enables preparation of symmetrical dienes, as long as the substrates have the same N substituent. Moreover, use of different N-substituted starting materials leads to formation of nonsymmetrical dienes. The reactivity of these dienes was evaluated in Diels - Alder reactions, showing a high reactivity.
Selectivities in the reaction of vicinal diimines and acyl chlorides
Wang, Zhixin,Chen, Ning,Xu, Jiaxi
supporting information; experimental part, p. 9690 - 9699 (2012/01/06)
The reaction of vicinal diimines and acyl chlorides in the presence of triethylamine produces 3-imino-β-lactams and/or bis-β-lactams chemo-, regio-, and stereoselectively, which are important intermediates in pharmaceutical and organic synthesis. The selectivities in the reaction have been investigated. The results indicate that all diimines react with various ketenes generated from acyl chlorides in the presence of triethylamine to give rise to cis-4-imino-β-lactams (mono-cis-β-lactams) diastereoselectively due to the electron-withdrawing property of the imino group in the vicinal diimines. Bis-β-lactams were obtained from diimines via the mono-cis-β-lactams as intermediates. Only ketenes with strong electron-donating substituents can react with the mono-cis-β-lactams to yield bis-β-lactams, affording a pair of C2-symmetric cis-bis-β- lactams with symmetric diimines, two or four pairs of diastereomeric bis-β-lactams with ketoaldehyde-derived unsymmetric diimines depending on the steric hindrance of their N-substituents. The current investigation provides very important information for the selective preparation of mono- and bis-β-lactams from vicinal diimines.
