Direct Transformation of Allylic and Benzylic Thiols, Thioethers, and Disulfides into Organolithium Compounds

Abstract

The reaction of allylic and benzylic thiols 1, disulfides 3, and thioethers 4 and 5 with an excess of lithium and a catalytic amount of 4,4′-di-tert-butylbiphenyl (DTBB, 5 mol%) afforded the corresponding allylic and benzylic organolithium reagents via reductive cleavage of the carbon–sulfur bond. The generated organolithium compounds gave the expected products 2 by reaction with several electrophiles followed by hydrolysis with water. The reaction conditions and the lithiation procedure (stepwise of Barbier-type process) depended on the starting sulfur containing compound.

Keywords:

• Lithium
• Organolithium
• Thiol
• Sulfide
• Disulfide
• Carbon–sulfur bond cleavage

Acknowledgments

This work was financially supported by the DGES from the Spanish Ministerio de Educación y Cultura (MEC) (project no. PB97-0133). P. M. thanks the University of Alicante for financial support.