为了开发2,6-二氟苯甲酰胺的绿色制备工艺以及探讨高温液态水中腈类物质的水解规律,研究了高温液态水中2,6-二氟苯睛无催化水解反应动力学.系统地研究了不同初始浓度、不同温度下2,6-二氟苯腈、2,6-二氟苯甲酰胺的水解反应动力学以及2,6-二氟苯甲酸的脱羧反应动力学.采用一级串联反应动力学方程拟合2,6-二氟苯腈的水解反应动力学数据,得到2,6-二氟苯腈和2,6-二氟苯甲酰胺水解反应的表观活化能分别为96.7kJ·mol<'-1>和75.4 kJ·mol<'-1>,2,6-二氟苯甲酸脱羧反应的表观活化能为184.3 kJ·mol<'-1>.所得结果不仅证明了从2,6-二氟苯腈出发无催化水解制备2,6-二氟苯甲酰胺的可行性,同时为腈类化合物在高温液态水中的水解规律提供了重要的基础数据.%2,6-Difluorobenzamide is an important organic reaction intermediate that is mainly used for syntb esizing fluor-benzylacylurea class pesticide intermediate. One of the methods for 2, 6difluorobenzamide preparation is inorganic acid/base catalyzed hydrolysis of 2, 6-difluorobenzonitrile, which causes serious waste water pollution. A green preparation technology of non-catalytic hydrolysis of 2,6-difluorobenzonitrile to 2, 6-difluorobenzamide in high temperature liquid water was studied in this work. 2,6-Difluorobenzonitrile hydrolysis is typical consecutive reactions with 2,6-difluorobenzamide and 2, 6-difluorobenzoic acid as intermediates and m-difluorobenzene as the final product. The hydrolysis kinetics of 2, 6-difluorobenzonitrile and 2, 6-difluorobenzamide, decarboxylation kinetics of 2, 6difluorobenzoic acid were determined at different initial concentrations and temperatures. With consecutive first-order kinetics models, the apparent activation energies evaluated were 96.7 kJ · mol-1 for 2, 6difluorobenzonitrile hydrolysis and 75.4 kJ · mol -1 for 2,6-difluorobenzamide hydrolysis, and 184.3 kJ · mol 1 for 2,6-difluorobenzoic acid decarboxylation. A yield of 64.27％ of 2,6-difluorobenzamide could be reached at 523.15 K and reaction time of 300 min, which proved the technical feasibility of non-catalytic hydrolysis of 2,6-difluorobenzonitrile to 2,6-difluorobenzamide in high temperature liquid water. The results could provide important basic data for the green preparation of 2,6-difluorobenzamide as well as the study of hydrolysis of nitriles in high temperature liquid water.
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