A CYCLOHEXANE SPACER FOR PHOSPHATE RECEPTORS

Abstract A cyclohexane tricarboxylic acid is shown to be a good spacer for phosphate guests. The combination of 8-aminochromenone-2-carboxamide groups with the cyclohexane spacer leads to a versatile receptor which sets six hydrogen bonds with either phosphonic acids or phosphates. Large association constants are obtained for this receptor in DMSO and methanol when tetraalkylammonium phosphates are used as guests.