Stoichiometric sensing to opt between gelation and crystallization.
A new class of organogelators having a cyclohexane-1a,3a-diol motif capable of congealing non-polar liquids was developed. These gelators underwent crystallization at low concentration and gelation above the critical gelation concentration (CGC) in the same solvent. The crystals and gel fibers were analyzed by single crystal XRD and PXRD respectively, which revealed their different modes of assembly. The XRD studies and thermogravimetric analysis (TGA) confirmed that the crystals contain a water of crystallization whereas the gel fibers do not. A systematic study revealed that when the concentration of the gelator exceeds that of adventitious water in the solvent, it congeals the solvent and when the concentration of the gelator is less than water, it undergoes crystallization. This unprecedented stoichiometric sensing behavior in deciding the mode of self-assembly offers a handle to opt between mutually competing gelation and crystallization. We have confirmed that the system can be biased to congeal or crystallize by varying the amount of water.
School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala 695016 (India) http://kms514.wix.com/kmsgroup.
Adiyala
A
Vidyasagar
School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala 695016 (India) http://kms514.wix.com/kmsgroup. kms@iisertvm.ac.in.
Kana M
KM
Sureshan
D002241:Carbohydrates / Q000737:chemistry; D003460:Crystallization / Q000379:methods; D003511:Cyclohexanols / Q000737:chemistry*; D005782:Gels / Q000737:chemistry*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D012997:Solvents / Q000737:chemistry; D014867:Water / Q000737:chemistry*
D002241:Carbohydrates; D003511:Cyclohexanols; D005782:Gels; D012997:Solvents; D014867:Water; C007192:cyclohexane-1,3-diol
crystals; gels; hydrogen bonding; self-assembly; supramolecular chemistry