Complexing and ion selective properties of some acid type phosphoryl podands. The crystal and molecular structures of 1,5-bis(2-dihydroxyphosphoryl-4-ethylphenoxy)-3-oxapentane dihydrate [(HO)2(O)P(C6H3CH2CH3)(OCH2CH2)2O (C6H3CH2CH3)P(O)(OH)2] · 2H2O

The synthesis of 1,5-bis(2-dihydroxyphosphoryl-4-ethylphenoxy)-3-oxapentane [(HO)2(O)P(C6H3CH2CH3)(OCH2CH2)2O(C6H3CH2CH3)P(O)(OH)2] (H4K2) and single crystal X-ray diffraction study of H4K2 · 2H2O (I) are described. The crystals are orthorhombic, a = 33.291(4) Å, b = 8.9374(10) Å, c = 8.1021(9) Å, V = 2410.6(5) Å3, Z = 4, space group Cmc21, R = 0.0484 for 2566 reflections with I > 2σ(I). In I, the molecules of H4K2 are hydrogen-bonded to two crystallographically independent H2O molecules to give neutral conglomerates H4K2 · 2H2O. The electroanalytical characteristics of poly(vinyl chloride) membranes based on H4K2 were tested. Cu2+ and Zn2+ complexes with H4K2 and Er3+, Nd3+, and complexes with H4K2, 1,5-bis[2-(dihydroxyphosphoryl-4-methoxy)phenoxy]-3-oxapentane, 1,5-bis[2-(dihydroxyphosphinyl)phenoxy]-3-oxapentane, and 1,8-bis[2-(dihydroxyphosphinyl)phenoxy]-3,6-dioxaoctane were prepared.