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Published on: April 9, 2018
A method for the reductive scission of heterocyclic thioethers
Thomas H Graham1, Wensheng Liu, Dong-Ming Shen
1Merck Research Laboratories, Merck & Co., Inc., P.O. Box 2000, Rahway, New Jersey 07065-0900, USA. thomas.graham@merck.com
Organic Letters
|November 10, 2011
Summary
A new method efficiently cleaves heterocyclic thioethers using mild conditions. This approach is compatible with various functional groups, offering a versatile alternative to traditional methods.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Heterocyclic thioethers are important structural motifs in organic chemistry.
- Traditional methods for thioether cleavage often lack chemoselectivity or require harsh conditions.
- Existing methods are incompatible with sensitive functional groups.
Purpose of the Study:
- To develop a mild and chemoselective method for the reductive scission of heterocyclic thioethers.
- To provide a versatile alternative to existing thioether cleavage techniques.
- To demonstrate the compatibility of the method with various functional groups.
Main Methods:
- Reductive scission of thioethers using a novel reagent system.
- Application to heterocycles with a thioether at the 2-position relative to a ring heteroatom.
- Demonstration of chemoselectivity with sensitive functional groups.
Main Results:
- Achieved generally high yields for the reductive scission of heterocyclic thioethers.
- The method is mild and chemoselective, tolerating sulfides, sulfones, and thiophenes.
- Benzyl esters, benzyl amides, and benzyl carbamates were found to be compatible with the reaction conditions.
Conclusions:
- A convenient and straightforward method for heterocyclic thioether cleavage has been established.
- This new method offers broader substrate scope compared to standard Raney nickel conditions.
- The developed protocol is valuable for synthetic chemists working with complex molecules.
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