Low molecular mass gelators are molecules whose heated solutions are homogeneous, but when cooled to room temperature form a gel. The test tubes below contain ethyl acetate with a low concentration of a gelator.
We were interested in synthesizing several gelators to investigate what structural properties influenced the ability of molecule to make a good gelator.
We have chemically attached a long hydrocarbon chain to various amino acid derivatives (of isoleucine*, phenylalanine, leucine and threonine), and tested their ability to act as gelators. The reaction on the right summarizes the preparation of the gelators.
Derivatives of isoleucine and phenylalanine produced the best gelators, while derivatives of leucine and threonine did not cause gelation.
*Hanabusa, Kenji; Hiratsuka, K; Kimura, M; and Shirai, H. "Easy Preparation and Useful Character of Organogel Electrolytes Based on Low Molecular Weight Gelator." Chem. Mater. (1999), Volume 11, pages 649-655.