Number of the records: 1
Solvent-free, catalyst-free aza-Michael addition of cyclohexylamine to diethyl maleate: reaction mechanism and kinetics
- 1.
SYSNO ASEP 0482881 Document Type J - Journal Article R&D Document Type Journal Article Subsidiary J Článek ve WOS Title Solvent-free, catalyst-free aza-Michael addition of cyclohexylamine to diethyl maleate: reaction mechanism and kinetics Author(s) Bláha, Michal (UMCH-V) RID
Trhlíková, Olga (UMCH-V) RID, ORCID
Podešva, Jiří (UMCH-V) RID
Abbrent, Sabina (UMCH-V) RID, ORCID
Steinhart, Miloš (UMCH-V) RID
Dybal, Jiří (UMCH-V) RID, ORCID
Dušková-Smrčková, Miroslava (UMCH-V) RID, ORCIDSource Title Tetrahedron. - : Elsevier - ISSN 0040-4020
Roč. 74, č. 1 (2018), s. 58-67Number of pages 10 s. Language eng - English Country GB - United Kingdom Keywords Aza-Michael addition ; solvent-free ; catalyst-free Subject RIV CD - Macromolecular Chemistry OECD category Polymer science Institutional support UMCH-V - RVO:61389013 UT WOS 000418728200008 EID SCOPUS 85035193735 DOI https://doi.org/10.1016/j.tet.2017.11.033 Annotation The aza-Michael reaction is the addition of an amine to an electron deficient C=C double bond. This reaction is also used in the synthesis of precursors of polymeric networks. In this study, we paid attention to the kinetics and mechanism of the aza-Michael addition of cyclohexylamine (CHXA) to diethyl maleate (DEM) performed as a solvent-free, catalyst-free reaction and to concurrent reactions. In situ Raman spectroscopy, NMR spectroscopy and gas chromatography/mass spectrometry have shown the occurrence of three simultaneous reactions: (i) the aza-Michael addition of CHXA to DEM leading to diethyl 2-(cyclohexylamino)succinate, (ii) isomerization of DEM to diethyl fumarate (DEF), and (iii) the aza-Michael addition of CHXA to DEF formed by the reaction (ii). All of these reactions proceed with third order kinetics, first order in DEM or DEF and second order in CHXA. We propose a kinetic model that allows kinetic constants to be estimated. Furthermore, a numerical solution of the set of differential equations confirms the expected kinetic equations of reactions (i) and (ii) and gives values of rate constants comparable to the estimated ones. A DFT mechanistic study illustrates the structure of the reaction intermediates and transition states of all reactions and explains the contribution of the second amine molecule in the reaction mechanism. Workplace Institute of Macromolecular Chemistry Contact Eva Čechová, cechova@imc.cas.cz ; Tel.: 296 809 358 Year of Publishing 2019
Number of the records: 1