Synthesis, structural characterization, and thermal properties of alkaline (earth) compounds derived from 2,4-dinitroimidazole

Abstract

Eight alkaline and alkaline-earth compounds derived from 2,4-dinitroimidazole (2,4-HDNI) were synthesized and characterized by elemental analysis, FT-IR, and TG–DSC, of which K(2,4-DNI) (1), Rb(2,4-DNI)(2,4-HDNI)(H₂O)₂ (2), and Ba(2,4-DNI)₂(H₂O)₄ (3) were characterized by single-crystal X-ray diffraction analysis. All the three compounds were crystallized from water, but 1 was an anhydrate. The coordination number in 1 and 3 is 10, but in 2 is 9. The 2,4-DNI adopts either η³, η², or η¹ coordination modes depending on the metal cation. In 3, there is an inversion center located on the metal. Only in 2 does water play an important role for the construction of the structure; in 3 it is a hydrogen bonding participant. TG–DSC analyses of 1 were also performed, and non-isothermal decomposition reaction kinetics were obtained.

Keywords:

• 2,4-Dinitroimidazole
• Main group metal compound
• Crystal structure
• Thermal behavior
• Kinetics

Acknowledgments

The authors thank the Department of Lab Construction and Administration of Shaanxi Normal University and National Defense Key Laboratory of Propellant and Explosive Combustion of China for providing financial support.