Thiourea derived Tröger's bases as molecular cleft receptors and colorimetric sensors for anions.

Thiourea-functionalized Tröger's base receptors 1 and 2 have been synthesized and evaluated as novel for the recognition of anions. Receptor 2 gave rise to significant changes in the absorption spectrum upon titration with AcO(-) and H2PO4(-) and acted as a colorimetric sensor for F(-), the interaction of which was also evaluated using (1)H NMR spectroscopy.