Selective colorimetric and fluorescent detection of HSO4- with sodium(I), magnesium(II) and aluminium(III) xanthone-crown ether complexes.

Xanthone-crown ether (1) reacts with NaClO(4), Mg(ClO(4))(2) and Al(ClO(4))(3) forming the one-dimensional chain dinuclear polymer [Na(2).1.(ClO(4))(2)] (2), the mononuclear complex Mg.1.(H(2)O)(2)(2) (3) and an interesting sandwich complex Al.(1)(2).(H(2)O)(6)(3) (4) with different ratios of metal-to-ligand, respectively. The anion recognition experiment results show that the magnesium complex (3) is a good colorimetric and fluorescent detector for HSO(4)(-) with high sensitivity and selectivity.