Two phosphate-imidazole complexes with and without a hydrogen-bonded guest molecule.

The molecular structures of the complexes imidazolium 6,6'-di-tert-butyl-4,4'-dimethyl-2,2'-thiodiphenyl phosphate, C(3)H(5)N(2)(+).C(22)H(28)O(4)PS(-), (I), and imidazolium 6,6'-di-tert-butyl-4,4'-dimethyl-2,2'-thiodiphenyl phosphate diisopropyl hydrazodicarboxylate hemisolvate, C(3)H(5)N(2)(+).C(22)H(28)O(4)PS(-).0.5C(8)H(16)N(2)O(4), (II), have been determined. While (I) forms the expected hydrogen-bonded chain utilizing the two imidazole N-bound H atoms, in (II), the substituted hydrazine solvent molecule inserts itself between the chains. Compound (I) exhibits a strong N-H...O hydrogen bond, with an N...O distance of 2.603 (2) A. The hydrazine solvent molecule in (II) lies about a twofold axis and the N-bound H atoms are involved in bifurcated hydrogen bonds with phosphate O atoms. A C-bound H atom of the imidazolium cation is involved in a C-H...O interaction with a carbonyl O atom of the hydrazine solvent molecule.