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Intermolecular Morita-Baylis-Hillman vs. an intramolecular Rauhut-Currier reaction
Rakesh Kumar Verma1, Mansingh Bairwa1, Juli Saini1
1Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi-221005, India. kishorbharadwaj@bhu.ac.in.
Organic & Biomolecular Chemistry
|August 4, 2026
Summary
Chemoselective trapping of enolates enables control over Morita-Baylis-Hillman (MBH) reactions, favoring intermolecular addition over intramolecular Rauhut-Currier (RC) reactions. This method offers new synthetic possibilities for organic chemistry.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- The Morita-Baylis-Hillman (MBH) reaction is a versatile carbon-carbon bond-forming reaction.
- The Rauhut-Currier (RC) reaction is another important conjugate addition reaction.
- Controlling the chemoselectivity between these related reactions is synthetically valuable.
Purpose of the Study:
- To develop a method for chemoselective enolate trapping.
- To favor intermolecular MBH (1,2) addition over intramolecular RC (1,4) addition.
- To explore the scope and limitations of this chemoselective strategy.
Main Methods:
- Utilizing the sensitivity of MBH reactions.
- Employing sluggish acrylamide as an enolate source.
- Synthesizing tethered acrylamide and enone precursors.
Main Results:
- Complete selectivity for intermolecular MBH reaction observed with acrylate and acrylonitrile tethered acrylamide.
- Some reactivity for intramolecular RC reaction observed with the corresponding enone.
- Reversal of selectivity demonstrated by modifying the substrate structure.
- Successful achievement of intramolecular RC reaction using N-alkylated precursors.
Conclusions:
- A novel method for chemoselective enolate trapping has been established.
- The developed method allows preferential formation of intermolecular MBH adducts.
- The findings open new avenues for exploring MBH and RC reactions and their applications.
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