Theoretical Studies on Intermolecular Interactions of 4-Amino-5-nitro-1,2,3-triazole Dimers

Seven optimized configurations and their electronic structures of 4-amino-5-nitro- 1,2,3-triazole dimers on their potential energy surface have been obtained by using density functional theory （DPT） method at the B3LYP/6-311＋＋G＊＊ level. The maximum intermolecular interaction energy is -35.42 kJ/mol via the basis set superposition error-correction （BSSE） and zero point energy-correction （ZPE）. Charge transfers between the two subsystems are small. The vibration analysis of optimized configurations was performed, and the thermodynamic property changes from monomer to dimer have been obtained with the temperature ranging from 200 to 800 K on the basis of statistical thermodynamics. It is found that the hydrogen bonds contribute to the dimers dominantly, and the extent of intermolecular interaction is mainly determined by the hydrogen bonds＇ strength rather than their number. The dimerization processes of Ⅳ, Ⅴand Ⅵ can occur spontaneously at 200 K.

A Double Azole-bridged Dinuclear Copper(Ⅱ) Complex Containing 4-Pyridyl-NH-1,2,3-triazoles: Synthesis, Structure and Magnetism

A new dinuclear copper(Ⅱ)compound[Cu2(CH3COO)2(L)2(H2O)2]·4H2O(1,HL=4-pyridyl-NH-1,2,3-triazole)has been synthesized and characterized.Single-crystal X-ray diffraction showed that complex 1 crystallizes in monoclinic space group P21/c with a=0.8427(1),b=1.0981(1),c=1.3610(1)nm,β=93.364(4)°,V=1.2573(1)nm^3,Mr=643.56,Z=2,Dc=1.700 g/cm^3,μ=1.760 mm-1,R=0.0376,wR=0.0981,and possesses a planar Cu2N4 six-membered ring,in which both Cu(Ⅱ)ions are bridged by two 1,2,3-triazole ligands.The neighboring dinuclear molecules are bound by strong intermolecular hydrogen bonds to create 1-D chains expanding along the b axis,which further form a 3-D supramolecular framework.Magnetic susceptibility measurement indicated the presence of weak antiferromagnetic interactions within the complex.The best fit using spin Hamiltonian yields the magnetic coupling constant J=–14.82 cm^-1 above 30 K.The magnetic data are compared to those obtained for related double diazine bridged dinuclear copper(Ⅱ)complexes and magnetostructural correlations are discussed.

Design,synthesis and antimicrobial activities of 1,2,3-triazole derivatives

Fifteen 1-（4-substituted phenyl）-4-（4-bromophenyl）-5-（halo-o-hydroxyphenyl）imino-1,2,3-triazoles were designed and synthe- sized based on rational combination of 1,2,3-triazoles and （halo）o-hydroxyphenyl group according to the superposition principle of reinforcement of biological activities. All the compounds were tested to an in vitro antimicrobial screening against M.a. and E.c.. Compounds IIe-IIo exhibited more potent antimicrobial activities against M.a. and E.c. than triclosan and fluconazole, which provided valuable information to further study of novel antimicrobial research.

Molecular Design and Property Prediction of High Density 4-Nitro-5-(5-nitro-1,2,4-triazol-3-yl)-2H-1,2,3-triazolate Derivatives as the Potential High Energy Explosives

To search for potential energetic materials with large energy density and acceptable thermodynamics and kinetics stability,twelve derivatives of 4-nitro-5-(5-nitro-1,2,4-triazol-3-yl)-2H-1,2,3-triazolate(named A~L)are designed and analyzed by using density functional theory(DFT)calculations at the B3LYP/6-311G**level of theory.The molecular heats of formation(HOF),electronic structures,impact sensitivity(H_(50)),oxygen balance(OB)and density(ρ)are investigated by isodesmic reaction method and physicochemical formulas.Furthermore,the detonation velocity(D)and detonation pressure(P)are calculated to study the detonation performance by Kamlet-Jacobs(K-J)equation.These results show that new molecule J(H_(50)=36.9 cm,ρ=1.90g/cm^(3),Q=1912.46 cal/g,P=37.82 GPa,D=9.22 km/s,OB=0.00),compound A(H_(50)=27.9 cm,ρ=1.93 g/cm^(3),Q=1612.93 cal/g,P=38.90 GPa,D=9.19 km/s)and compound H(H_(50)=37.3 cm,ρ=1.97 g/cm^(3),Q=1505.06cal/g,P=37.20 GPa,D=9.01 km/s)present promising effects that are far better RDX and HMX as the high energy density materials.Our calculations can provide useful information for the molecular synthesis of novel high energy density materials.

Theoretical Study on the Nitrogen-rich Derivatives Based on 1,2,4-Triazole and 1,2,3-Triazole Rings:an Extended Family of Power Performance Energetic Materials

The geometric and electronic structures of the derivatives of 4-nitro-5-(5-nitroimino-1,2,4-triazol-3-yl)-2H-1,2,3-triazolate(named A~J)are explored employing density functional theory(DFT)calculations at the B3LYP/6-311G^(**)level of theory.Based on the optimized molecular structures,the heats of formation(HOF)are obtained,and the electronic properties,density and molecular sensitivity by characteristic heights(H_(50))are discussed.Besides,the detonation performances(detonation velocity,detonation pressure)are estimated via Kamlet-Jacobs(K-J)formula.Compounds B(H50=29.4 cm,ρ=1.91 g/cm^(3),Q=1563.04 cal/g,P=36.05 GPa,D=8.95 km/s)and H(H_(50)=31.9 cm,ρ=1.80 g/cm^(3),Q=1610.09 cal/g,P=37.31 GPa,D=9.12 km/s)have positive HOFs and remarkable insensitivity and good detonation performance,strongly suggesting them as the acceptable new-type explosive.The initiating power surpasses conventional primary explosives,such as HMX.The outstanding detonation power of compounds B and H contributes to its future prospects as a promising green primary explosive.

Synthesis of 2（5H）-Furanone Derivatives with Bis-1,2,3-triazole Structure

A series of new chiral 2（5H）-furanone derivatives containing bis-l,2,3-triazole moiety were designed and syn- thesized from （5S）-5-alkoxy-3,4-dihalo-2（5H）-furanones 1, dicarboxyl amino acids 2, propargyl bromide, and or- ganic azides 5 under mild conditions via the sequential three steps, including asymmetric Michael addi- tion-elimination, substitution and no-ligand click reaction. Twelve new intermediates, including N-[5-alkoxy- 2（5H）-furanonyl] dicarboxyl amino acids 3 and their corresponding propargyl esters 4, and twelve target molecules 6 were characterized by FTIR, 1H NMR, 13C NMR, MS and elemental analysis. The influences of different syn- thetic conditions and substrates in each step were investigated. The research provides a new method and idea for the synthesis of 2（5H）-furanone compounds with polyheterocyclic structure due to the diversities of four basic unit molecules.