Abstract: | The molecular structures of the complexes imidazolium 6,6′‐di‐tert‐butyl‐4,4′‐dimethyl‐2,2′‐thiodiphenyl phosphate, C3H5N2+·C22H28O4PS?, (I), and imidazolium 6,6′‐di‐tert‐butyl‐4,4′‐dimethyl‐2,2′‐thiodiphenyl phosphate diisopropyl hydrazodicarboxylate hemisolvate, C3H5N2+·C22H28O4PS?·0.5C8H16N2O4, (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) Å. 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. |