Exploiting the Imidazolium Effect in Base-free Ammonium Enolate Generation: Synthetic and Mechanistic Studies

Claire M. Young; Daniel G. Stark; Thomas H. West; James E. Taylor; Andrew D. Smith

doi:10.1002/anie.201608046

Exploiting the Imidazolium Effect in Base-free Ammonium Enolate Generation: Synthetic and Mechanistic Studies

Claire M. Young, Daniel G. Stark, Thomas H. West, James E. Taylor, Andrew D. Smith

Department of Chemistry

University of St Andrews

Research output: Contribution to journal › Article › peer-review

45 Citations (SciVal)

85 Downloads (Pure)

Abstract

N-Acyl imidazoles and catalytic isothiourea hydrochloride salts function as ammonium enolate precursors in the absence of base. Enantioselective Michael addition–cyclization reactions using different α,β-unsaturated Michael acceptors have been performed to form dihydropyranones and dihydropyridinones with high stereoselectivity. Detailed mechanistic studies using RPKA have revealed the importance of the “imidazolium” effect in ammonium enolate formation and have highlighted key differences with traditional base-mediated processes.

Original language	English
Pages (from-to)	14394-14399
Number of pages	6
Journal	Angewandte Chemie - International Edition
Volume	55
Issue number	46
DOIs	https://doi.org/10.1002/anie.201608046
Publication status	Published - 7 Nov 2016

Keywords

imidazolium effect
isothiourea catalysis
mechanistic study
Michael addition
N-acyl imidazoles

ASJC Scopus subject areas

Catalysis
General Chemistry

Access to Document

10.1002/anie.201608046

Acyl Imid_ACIE_Revised_Final
This is the peer-reviewed version of the following article: Young, CM, Stark, DG, West, TH, Taylor, JE & Smith, AD 2016, 'Exploiting the Imidazolium Effect in Base-free Ammonium Enolate Generation: Synthetic and Mechanistic Studies' Angewandte Chemie - International Edition, vol 55, no. 46, pp. 14394-14399 which has been published in final form at https://doi.org/10.1002/anie.201608046. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
Accepted author manuscript, 939 KB

Cite this

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Exploiting the Imidazolium Effect in Base-free Ammonium Enolate Generation: Synthetic and Mechanistic Studies

Abstract

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James Taylor

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Exploiting the Imidazolium Effect in Base-free Ammonium Enolate Generation: Synthetic and Mechanistic Studies

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Keywords

ASJC Scopus subject areas

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James Taylor

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