AI Article Synopsis
- - N-Acyl imidazoles and isothiourea hydrochloride salts can create ammonium enolate precursors without needing a base.
- - Researchers conducted enantioselective Michael addition-cyclization reactions that produced dihydropyranones and dihydropyridinones with high stereoselectivity using various α,β-unsaturated Michael acceptors.
- - Mechanistic studies using RPKA showed how the "imidazolium" effect is crucial for ammonium enolate formation and pointed out differences from traditional methods that use bases.
Article 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.
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| http://dx.doi.org/10.1002/anie.201608046 | DOI Listing |
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