A new energetic material,4,5-dimethoxy-2-(dinitromethylene)imidazolidine(DMDNI),was synthesized by the reaction of 4,5-dihydroxyl-2-(dinitromethylene)-imidazolidine(DDNI) and methanol,and structurally characte...A new energetic material,4,5-dimethoxy-2-(dinitromethylene)imidazolidine(DMDNI),was synthesized by the reaction of 4,5-dihydroxyl-2-(dinitromethylene)-imidazolidine(DDNI) and methanol,and structurally characterized by single crystal X-ray diffraction.DMDNI crystallized in triclinic space group P1,with crystal data a=0.4324(4) nm,b=1.3599(11) nm,c=1.7503(14) nm,α=77.406(14)°,β=84.494(15)°,γ=87.976(14)°,V=0.9997(14) nm 3,Z=4,μ=0.140 mm-1,F(000)=488,D c =1.556 g/cm ^3,R 1 =0.0773 and wR 2 =0.1574.Thermal decomposition of DMDNI was studied,and its thermal decomposition process was divided into two stages.The first stage was a melting process and the second stage was an exothermic decomposition process.The enthalpy,apparent activation energy and pre-exponential constant of the exothermic decomposition reaction are-491.5 J/g,142.3 kJ/mol and 10 14.24 s^-1,respectively.The critical temperature of thermal explosion is 162.47 °C.DMDNI has a lower thermal stability than DDNI but it is close to that of 4,5-diacetoxyl-2-(dinitromethylene)-imidazolidine(DADNI).展开更多
A highly efficient and environmentally benign protocol for the synthesis of 2-amino-5,7-dimethoxy-4- aryl/alkyl-4H-chromene-3-carbonitrile derivatives by one-pot three-component coupling reacting of aromatic aldehydes...A highly efficient and environmentally benign protocol for the synthesis of 2-amino-5,7-dimethoxy-4- aryl/alkyl-4H-chromene-3-carbonitrile derivatives by one-pot three-component coupling reacting of aromatic aldehydes, malononitrile and 3,5-dimethoxy phenol under reflux condition has been developed in aqueous EtOH media using Na2O-Al2O3-P2O5 glass-ceramic system.展开更多
A new azafluorenone (onychine) alkaloid, 6,7-dimethoxy-5-hydroxy-onychine, was isolated from the stem and branch of Alphonsea monogyma. Its structure was established mainly on the basis of spectral analysis.
A new azafluorenone (onychine) alkaloid. 6.7-dimethoxy-5-hydroxy onychine N-oxide. was isolated from the stem and branch of Alphonsea monogyma. Its structure was established on the basis of spectral and chemical anal...A new azafluorenone (onychine) alkaloid. 6.7-dimethoxy-5-hydroxy onychine N-oxide. was isolated from the stem and branch of Alphonsea monogyma. Its structure was established on the basis of spectral and chemical analysis.展开更多
基金Supported by the National Natural Science Foundation of China(No.20803058)the Basal Science Foundation of National Defense(No.B0920110005)+1 种基金the Science Program Foundation of Shaanxi Province,China(No.2011kjxx31)the Education Committee Foundation of Shaanxi Province,China(No.2010JK881)
文摘A new energetic material,4,5-dimethoxy-2-(dinitromethylene)imidazolidine(DMDNI),was synthesized by the reaction of 4,5-dihydroxyl-2-(dinitromethylene)-imidazolidine(DDNI) and methanol,and structurally characterized by single crystal X-ray diffraction.DMDNI crystallized in triclinic space group P1,with crystal data a=0.4324(4) nm,b=1.3599(11) nm,c=1.7503(14) nm,α=77.406(14)°,β=84.494(15)°,γ=87.976(14)°,V=0.9997(14) nm 3,Z=4,μ=0.140 mm-1,F(000)=488,D c =1.556 g/cm ^3,R 1 =0.0773 and wR 2 =0.1574.Thermal decomposition of DMDNI was studied,and its thermal decomposition process was divided into two stages.The first stage was a melting process and the second stage was an exothermic decomposition process.The enthalpy,apparent activation energy and pre-exponential constant of the exothermic decomposition reaction are-491.5 J/g,142.3 kJ/mol and 10 14.24 s^-1,respectively.The critical temperature of thermal explosion is 162.47 °C.DMDNI has a lower thermal stability than DDNI but it is close to that of 4,5-diacetoxyl-2-(dinitromethylene)-imidazolidine(DADNI).
基金the Najafabad Branch,Islamic Azad University for financial support of this research
文摘A highly efficient and environmentally benign protocol for the synthesis of 2-amino-5,7-dimethoxy-4- aryl/alkyl-4H-chromene-3-carbonitrile derivatives by one-pot three-component coupling reacting of aromatic aldehydes, malononitrile and 3,5-dimethoxy phenol under reflux condition has been developed in aqueous EtOH media using Na2O-Al2O3-P2O5 glass-ceramic system.
文摘A new azafluorenone (onychine) alkaloid, 6,7-dimethoxy-5-hydroxy-onychine, was isolated from the stem and branch of Alphonsea monogyma. Its structure was established mainly on the basis of spectral analysis.
文摘A new azafluorenone (onychine) alkaloid. 6.7-dimethoxy-5-hydroxy onychine N-oxide. was isolated from the stem and branch of Alphonsea monogyma. Its structure was established on the basis of spectral and chemical analysis.