Crystal Structure of a Proton-Transfer Self-Associated Compound from 1,10-Phenanthroline-2,9-dicarboxylic Acid and Creatinine

Abstract

The crystal structure of (creatH)⁺ (phendcH)^-·H₂O (creat = creatinine, phendcH₂ = 1,10-phenanthroline-2,9-dicarboxylic acid) was determined by the X-ray diffraction method. This compound crystallized in the triclinic system, space group P1, with two formula units in the unit cell. The unit cell parameters were: a = 7.7265(7)Å, b = 10.7685(10)Å, c = 11.5397(11)Å, with α = 75.870(2)°, β = 71.165(2)° and γ = 77.107(2)°. The final R value was 0.0521 for 3998 measured reflections. Proton transfer resulted in the formation of a self-associated system consisting of cationic and anionic units connected through H-bonding and ion-pairing simultaneously.