A mechanochemical approach for organocatalysis and improved synthesis of gemini surfactants

Abstract

Mechanochemistry and organocatalysis provide green synthetic methods for chemical reactions. Reported herein are Morita-Baylis-Hilman reactions co-catalyzed by 1,4-diazabicyclo[2.2.2]octane, DABCO, and 1-(4-(3-(3,5-bis(trifluoromethyl)phenyl)thioureido)-benzyl)-1-methylpyrrolidin-1-ium hexafluorophosphate using a mechanochemical approach known as Liquid Assisted Grinding, LAG. These room temperature reactions used methanol as a liquid additive to achieve an 85.7 % conversion and 14.8 % isolated yields, which is a slight improvement over conventional methods.

Gemini cationic surfactants have a lower critical micelle concentration (CMC) when compared to conventional analogues. This led to many improvements in materials such as soaps, detergents, wetting agents and foaming agents. There is a particular interest from a physical and material chemistry standpoint on how gemini cationic surfactants will behave with other surfactants in mixed micellular systems. Previously reported syntheses of quaternary amine gemini surfactants in the literature noted long reaction times, poor yields and large solvent use, making large scale production troublesome. Reported herein is an improved synthesis of mcm type cationic gemini surfactants using microwave irradiation.