2,4-二硝基苯磺酰胺的合成工艺改进

以2,4-二硝基苯胺为原料,依次经重氮化和磺化反应制得2,4-二硝基苯磺酰氯(3);3与氨水反应合成了2,4-二硝基苯磺酰胺(4),其结构经~1H NMR,~(13)C NMR,EI-MS和元素分析确证。研究了反应时间,反应温度,溶剂,物料比{r[n(氨水)∶n(3)]}和加料次序对4收率的影响。结果表明:在最佳反应条件[THF为溶剂,氨水75mmol,r=1.5,于10~30℃反应3 h]下合成4,收率91.3%。     

Entanglement and decoherence in a quantum dimer

The dynamical properties of quantum entanglement in an integrable quantum dimer are studied in terms of the reduced-density linear entropy with various coupling parameters and total boson numbers. The characteristic time of decoherence process in the early-time evolution of the linear entropy is obtained, indicating that the characteristic time and the corresponding entropy exhibit a maximum near the position of the corresponding classical separatrix energy.