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Condition-Modulated Regiodivergent Transfer Hydrogenation of Epoxide using Methanol as Sustainable H2 Source
Ishani Borthakur1, Srabani Nandi1, Isha Garg2
1Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, 208016, India.
Chemsuschem
|June 4, 2025
Summary
This study presents a novel method for the regiodivergent transfer hydrogenation of epoxides using methanol as a hydrogen source. Reaction conditions, not the catalyst, control regioselectivity, enabling selective epoxide functionalization.
Area of Science:
- Organic Chemistry
- Catalysis
- Sustainable Chemistry
Background:
- Epoxide reduction is crucial for organic synthesis.
- Methanol as a hydrogen source faces challenges like methoxylation.
- Selective epoxide functionalization requires controlled reduction.
Purpose of the Study:
- To develop a regiodivergent transfer hydrogenation of epoxides using methanol.
- To control regioselectivity by modulating reaction conditions with a single catalyst.
- To extend the methodology for one-pot synthesis.
Main Methods:
- Utilized a single Iridium(III) catalyst for epoxide transfer hydrogenation.
- Employed methanol as a sustainable hydrogen source.
- Manipulated reaction conditions (additives like KOTf, TFE, KOH, tAmOH) to control regioselectivity.
Main Results:
- Achieved unprecedented regiodivergent transfer hydrogenation of epoxides.
- Demonstrated anti-Markovnikov selectivity with KOTf/TFE and Markovnikov selectivity with KOH/tAmOH.
- Successfully extended the method to a one-pot beta-methylation of alcohols.
Conclusions:
- Strategic modulation of reaction conditions enables selective epoxide functionalization.
- The developed method offers a sustainable and versatile approach for organic synthesis.
- Mechanistic studies elucidated the factors governing regioselectivity.
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