Crystallographic, 1H NMR and CD studies of sterically strained thiourea anion receptors possessing two stereogenic centres

The synthesis and structural characterisation of three chiral bis-naphthalene thiourea receptors (1-3) derived from (R)-(+)-1-(1-naphthyl)ethylamine and (S)-(-)-1-(1-naphthyl)ethylamine are reported along with spectroscopic studies to screen their potential as anion receptors/sensors. Their solid state structures were analysed by X-ray crystallography and their ability to bind anions such as acetate and phosphate in DMSO solution investigated by H-1 NMR, absorption, fluorescence and circular dichroism spectroscopy.