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Reductive coupling of allenoates with aldehydes catalyzed by halogenotin hydride
Itaru Suzuki1, Yu-Ya Hamada2, Yuki Uji2
1Research Center for Environmental Preservation, Osaka University, 2-4 Yamadaoka, Suita, Osaka 565-0871, Japan. shibata@epc.osaka-u.ac.jp.
Organic & Biomolecular Chemistry
|July 5, 2022
Summary
Researchers developed a new hydrostannylation method for allenoates, creating allylic stannanes and alcohols. This versatile organotin chemistry enables the synthesis of complex lactones and oxacycles.
Area of Science:
- Organic Chemistry
- Organometallic Chemistry
Background:
- Hydrostannylation is a key reaction in organic synthesis.
- Developing efficient catalytic methods for hydrostannylation is crucial.
Purpose of the Study:
- To develop a novel hydrostannylation of allenoates using halogenotin hydrides.
- To explore the synthetic utility of the resulting allylic stannanes and alcohols.
- To establish a catalytic protocol for the synthesis of lactones and oxacycles.
Main Methods:
- Hydrostannylation of allenoate 1 with dibutyltin dichloride hydride (Bu2SnClH).
- Coupling of allylic stannane (I) with aldehyde 2.
- Reductive coupling using silane and catalytic Bu2SnClH.
- Oxidation of products to form oxacycles.
Main Results:
- Synthesis of allylic stannane (I) from allenoate 1.
- Formation of allylic alcohol 3 via reductive coupling.
- Application of the catalytic protocol to synthesize lactone 4.
- Oxidation of products 3 and 4 to yield oxacycles 5 and 6.
Conclusions:
- A new hydrostannylation of allenoates was successfully developed.
- The developed methods provide access to valuable allylic stannanes, alcohols, lactones, and oxacycles.
- The catalytic protocol offers an efficient route for synthesizing complex cyclic compounds.
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