Mechanistic Exploration of Umpolung Guided Stetter-Aldol Reaction and Its Dependence on the Choice of Imine

0567234 - ÚOCHB 2024 RIV DE eng J - Journal Article
Barman, D. - Lo, Rabindranath - Maiti, D. K. - Manna, D. - Ghosh, T.
Mechanistic Exploration of Umpolung Guided Stetter-Aldol Reaction and Its Dependence on the Choice of Imine.
ChemistrySelect. Roč. 8, č. 1 (2023), č. článku e202204558. ISSN 2365-6549. E-ISSN 2365-6549
Institutional support: RVO:61388963
Keywords : umpolung * Breslow intermediate * free energy profile * density functional theory * isoquinoline
OECD category: Physical chemistry
Impact factor: 2.1, year: 2022
Method of publishing: Limited access
https://doi.org/10.1002/slct.202204558

NHC-catalyzed Stetter-aldol reaction for the synthesis of hydroxyindanone takes place via umpolung reactions of phthalaldehyde followed by intramolecular aldol reaction when N-tert-butoxycarbonyl (Boc) imine is used and this leads to the formation of [4+1] annulation product. However, this mechanism doesn't follow similar sequence in case of N-tosyl-alpha,beta-unsaturated ketimine and [4+2]-annulation product is found as the sole product for the latter case through formation of aza-“Berslow intermediate“. In this study we have used state of the art computational techniques to find out the possible reason for the difference in product and the detailed mechanistic pathway for the above two reactions. Thus, we explain the mechanism for obtaining the selective annulation product ([4+1] vs [4+2]) that can help chemists to design and synthesize a new series of compounds.
Permanent Link: https://hdl.handle.net/11104/0338512