1,3-indane-based chromogenic calixpyrroles with push-pull chromophores: synthesis and anion sensing

Org Lett. 2006 Feb 2;8(3):359-62. doi: 10.1021/ol0521782.

Abstract

[structure: see text]. Knoevenagel condensation of 2-formyl-octamethylcalix[4]pyrrole with selected 1,3-indanedione derivatives yields calix[4]pyrrole anion sensors with push-pull chromophores displaying strong intramolecular charge transfer. The push-pull feature results in augmented signal output as well as in dramatic changes in anion selectivity exemplified by a 50-fold increase in acetate vs chloride selectivity compared to the parent calix[4]pyrrole.