Chiral surfactants to enhance stereoselectivity in asymmetric catalytic sulfoxidation in water

Abstract

Chiral surfactants can provide asymmetric environments in water that can enhance the stereoselectivity of chiral metal catalysts. Due to the high dynamic nature of micelles, this specific field of research has been seldom investigated. The design of the surfactant and its interaction with the catalyst is crucial to improve stereoselectivity. We report a series of chiral surfactants bearing rigid aromatic hydrophobic units based on the BINOL scaffold decorated with hydrophilic side chains. In particular, the use of anionic side chains provide better interaction with chiral Pt(II) catalysts due to ion pairing leading to improvements in the enantioselectivity of the sulfoxidation reaction of thioethers with hydrogen peroxide. This proof of concept contribution opens the way to the design of new classes of chiral designer surfactants that could be applied to move to water many classes of stereoselective reactions traditionally carried out in organic media.