Five-Membered Chemical Combo Gels

A novel multicomponent combination of chemicals that causes organic solvents to irreversibly gel up may allow scientists to begin tuning or designing other similar mixtures (J. Am. Chem. Soc., DOI: 10.1021/ja8002777). Organogelators, of which there are many types, are usually formed by one or two low-molecular-weight compounds, often discovered by accident, that cause a solution to gel as it cools. Organogels have numerous uses as functional soft materials, ranging from liquid crystals to sensors and even cosmetics. David Díaz Díaz (now at Dow Chemical in Horgen, Switzerland) and colleagues at the University of La Laguna, in Tenerife, Spain, also happened upon their organogelator system serendipitously while studying the tartaric acid-based racemic resolution of (±)-trans-1,2-diaminocyclohexane. In contrast with other organogelators, the new system is a combination of five readily available small molecules: L-tartaric acid, the diaminocyclohexane, methanol, hydrochloric acid, and water. A low concentration of this mixture rapidly and irreversibly gelatinizes numerous cold organic solvents when the solution is warmed. The discovery "opens the door for the design of new low-cost and efficient liquid multicomponent organogelators," the researchers write.