2，4-二硝基咪唑二甲基铵盐的制备及晶体结构

摘要

A new energetic salt of 2,4-dinitroimidazole ([(DNI)NH2 (CH3 ) 2 ]) was synthesized with yield of 62.7% by using 2,4-dinitroimidazole as starting materials.The structure of [(DNI)NH2 (CH3 )2 ] was characterized by IR, elemental analysis, fourcircle single crystal X-ray diffraction NMR.Results show that the crystal of title compound belongs to monoclinic system, space group C2/c with a =31.403 (5) Å,b =6.7133 (7) Å,c =22.769 (4) Å,α=90.00°,β=126.80 (3)°,γ=90.00°,V =3843.6(10) Å3 ,Z =16,Dc =1.404 g ・ cm-3 , F(000) =1696.0, μ(MoKα) =0.121 mm-1 .The molecule packing of [(DNI)NH2 (CH3 ) 2 ] is not compacted.Intra molecular and intermolecular hydrogen bonds are weak and the density is lower. Thermal properties were tested by TG-DSC.Results reveal that the [(DNI)NH2 (CH3 ) 2 ] shows good thermal stability.%以2，4-二硝基咪唑为原料，经中和、取代两步反应合成出了2，4-二硝基咪唑二甲基铵盐[（DNI） NH2（CH3）2]，产率为62．7％。用IR、1 H NMR及13 C NMR、元素分析和单晶X-射线衍射对其分子和晶体结构进行了表征。结果表明：该晶体属于单斜晶系，空间群C2/c，a＝31．403（5）Å，b＝6．7133（7）Å，c＝22．769（4）Å，α＝90．00°，β＝126．80（3）°，γ＝90．00°，V＝3843．6（10）Å3， Z＝16，Dc＝1．404 g・ cm-3，F（000）＝1696．0，μ（MoKα）＝0．121 mm-1。分子内及分子间氢键作用微弱，分子堆积不紧密，密度较小。并用TG-DSC对[（DNI）NH2（CH3）2]进行了热分解研究，表明其分解经过两步，熔点190．7℃，热稳定性良好。