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Cobalt-Catalysed Reductive Etherification Using Phosphine Oxide Promoters under Hydroformylation Conditions
Fábio G Delolo1,2, Johannes Fessler2, Helfried Neumann2
1Departamento de Química, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, MG 31270-901, Belo Horizonte, Brazil.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|January 12, 2022
Summary
A new cobalt-catalyzed method efficiently creates unsymmetrical ethers from aldehydes and alcohols using syngas. This phosphine-oxide-promoted reaction works under mild conditions and is scalable for broad synthetic applications.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Ether synthesis is crucial in organic chemistry.
- Developing efficient and mild synthetic routes remains an active area of research.
- Reductive methods offer alternative pathways for ether formation.
Purpose of the Study:
- To report a novel phosphine-oxide-promoted, cobalt-catalyzed reductive etherification.
- To utilize syngas (synthesis gas) as a reductant for ether synthesis.
- To demonstrate the preparation of diverse unsymmetrical ethers.
Main Methods:
- Cobalt-catalyzed reaction using a phosphine-oxide promoter.
- Employing syngas (CO/H2) as the reducing agent.
- Reaction of various aldehydes and alcohols.
Main Results:
- Successful synthesis of a broad range of unsymmetrical ethers.
- High functional group tolerance observed in substrates.
- Scalable to multigram quantities under mild conditions.
- Mechanistic studies indicated an acetalization-hydrogenation pathway.
Conclusions:
- The developed methodology provides an efficient route to unsymmetrical ethers.
- The use of syngas as a reductant offers a sustainable approach.
- The reaction is robust, scalable, and tolerant of diverse functional groups.
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