Improved Green Synthesis and Crystal Structures of Symmetrical Cationic Gemini Surfactants

Abstract

Gemini surfactants are composed of two hydrocarbon tails with corresponding polar headgroups, linked via a covalent spacer. The synthesis of these surfactants is a very active area of research due to their application as catalysts and other applied areas of study. The modification of green microwave techniques developed in our research on ionic liquids has resulted in the significant improvement of the synthesis of N,N ′-bis(dimethylalkyl)-α,ω-alkanediammonium dibromide (m–s–m type) symmetrical gemini surfactants. This approach utilizes a remarkably more economical, green, and sustainable methodology for the production of symmetrical gemini surfactants that can be utilized in numerous commercial applications. The improved synthetic approach of these gemini surfactants has led to the characterization of their crystalline packing for the first time ever using X-ray crystallographic analysis.

The partitioning of primary alcohols into the aggregates of gemini amphiphiles determined from diffusion NMR experiments

“…The symmetric m-s-m gemini surfactants were synthesized using either the method of Wettig and Verall 52,53 or the recently developed microwave method by Singer et al 62 Structures for the gemini surfactants are given in the Data Section (ESI †). Details concerning the synthesis of the surfactants have been described in our previous papers, [63][64][65] and are also available in the ESI.…”

Properties and Applications of Quaternary Ammonium Gemini Surfactant 12-6-12: An Overview

“…12-6-12 can also be synthesised in solvent mixtures such as the acetonitrile/toluene mixture [36]. The reaction time can be shortened using microwave radiation [37]. However, the most economical and ecological approach is to synthesise 12-6-12 under stoichiometric conditions at room temperature without a solvent [38].…”