Theoretical investigation of the mechanism of DMAP-promoted [4 + 2]-annulation of prop-2-ynylsulfonium with isatoic anhydride
- 11 January 2022
- journal article
- research article
- Published by Canadian Science Publishing in Canadian Journal of Chemistry
- Vol. 100 (4), 1-9
- https://doi.org/10.1139/cjc-2021-0174
Abstract
The mechanism for DMAP-promoted [4 + 2]-annulation of prop-2-ynylsulfonium with isatoic anhydride is investigated using the M06-2X functional. The reaction comprises isomerization of prop-2-ynylsulfonium in stage 1. Stage 2 includes DMAP-promoted deprotonation, nucleophilic addition, ring opening, and decarboxylation. Three steps of intramolecular cycloaddition, DMAP-promoted protonation, and dealkylation occur in stage 3, generating methylated DMAP and neutral thioether, which undergo double-bond isomerization to yield 3-methylthio-4-quinolone. The ability of DMAP to promote the reaction lies in the barrier decrease for alkyne isomerization, deprotonation/protonation of allenes, and dealkylation as effective bases for transferring protons and methyl groups. The roles of prop-2-ynylsulfonium and isatoic anhydride were demonstrated to be C2 and C4 synthons via Multiwfn analysis on the frontier molecular orbital. An alternative path was also confirmed by the Mayer bond order of the vital transition states.Keywords
This publication has 42 references indexed in Scilit:
- Enantioselectivity in Organocatalytic Cascade Double Michael Addition Reaction: A Theoretical StudyThe Journal of Physical Chemistry A, 2011
- Quantum Mechanical Investigations of Organocatalysis: Mechanisms, Reactivities, and SelectivitiesChemical Reviews, 2011
- Theoretical mechanistic study of TangPhos-catalyzed asymmetric γ addition of thiols to allenoatesJournal of Molecular Catalysis A: Chemical, 2011
- Universal Solvation Model Based on Solute Electron Density and on a Continuum Model of the Solvent Defined by the Bulk Dielectric Constant and Atomic Surface TensionsThe Journal of Physical Chemistry B, 2009
- Computational prediction of small-molecule catalystsNature, 2008
- Quantum Mechanical Continuum Solvation ModelsChemical Reviews, 2005
- Recent Advances in the Baylis−Hillman Reaction and ApplicationsChemical Reviews, 2003
- Molecular Interactions in Solution: An Overview of Methods Based on Continuous Distributions of the SolventChemical Reviews, 1994
- Solvent effect theories: Quantum and classical formalisms and their applications in chemistry and biochemistryJournal of Mathematical Chemistry, 1992
- Intermolecular interactions from a natural bond orbital, donor-acceptor viewpointChemical Reviews, 1988