4-氨基-5-硝基-1，3-二氟苯重氮化反应机理研究

Theoretical study of reaction mechanism of diazotization of 4-amino-5-nitro-1,3-difluorinbenzene

以4-氨基-1,3-二氟苯、乙酸酐和浓硝酸等为原料,合成了4-乙酰基-5-硝基-1,3-二氟苯,并且采用FT-IR和1H NMR对产物进行了表征.采用量子化学方法,探讨了重氮化反应过程中重氮盐形成的微观机理,采用密度泛函理论(Density Functional Theory)在B3LYP/6-311G**水平下搜索得到反应路径,并对各中间体、过渡态和产物进行几何优化、振动频率分析和标准热力学函数计算;反应路径经过IRC验证.在MP2/6-311G**水平上对所有中间体、过渡态和产物进行更精确的能量校对.

5-nitro-1, 3,difluorinbenzene was synthesized by diazotization of 4-amino-5-nitro- 1,3-difluofinbenzene and was characterized by FT-IR and ^1H NMR. On the basis of synthesis experiment, the theoretical study of reaction mechanism of the diazotization process was carried out and the reaction pathway has been studied with the density functional theory（DFT）method at the B3LYP/6-311G ^＊＊ level. The geometrical parameters of transition states（TS） were optimized; intrinsic reaction coordinate（IRC）calculations have also been performed to obtain further credible features. The frequency analysis of reactants, products, intermediates and transition states were calculated at the same level. The total energies of all geometries were rectified at the second-order Mφller-Plesset（MP2）/6-311G^＊＊ .