Cholesterol appended pyridinium ureas: a case of gel making and breaking for selective visual readout of F−
作者:Kumaresh Ghosh、Debasis Kar
DOI:10.1039/c2ob26631h
日期:——
Cholesterol appended pyridinium ureas 1 and 2 have been designed and synthesized. The unsymmetrical urea-based chemosensor 1 fluorimetrically distinguishes Fâ from the other anions examined in both CH3CN and DMSO with appreciable binding constant values. The pyridinium â based symmetrical compound 2 acts as a low molecular weight gelator (LMWG) in CHCl3 and is capable of detecting Fâ visually by breaking the gel. On the contrary, the chemosensor 1 in DMSO in the presence of tetrabutylammonium fluoride undergoes a change from sol to gel state that produces an unambiguous visual readout of Fâ.