The ground state tautomerism and excited state intramolecular proton transfer in two new molecular switches, namely N-(benzo[d]thiazol-2-yl)picolinamide and N-(benzo[d]thiazol-2-yl)isonicotinamide, are studied in acetonitrile by the combined use of steady state and time dependent spectroscopy and DFT calculations. Although, according to the theoretical calculations, two potential switching pathways are possible in N-(benzo[d]thiazol-2-yl)picolinamide, either through the pyridine or through the benzothiazole moiety, the experimental results show the same photodynamics as in N-(benzo[d]thiazol-2-yl)isonicotinamide. This indicates that the excited state proton transfer from the amide NH to the betzothiazole nitrogen is preferred in both compounds.

中文翻译：

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苯并噻唑吡啶啉/异烟酰胺分子开关：期望与现实


研究了两种新型分子开关 N-(苯并[d]噻唑-2-基)吡啶酰胺和 N-(苯并[d]噻唑-2-基)异烟酰胺的基态互变异构和激发态分子内质子转移。通过结合使用稳态和时间相关光谱以及 DFT 计算来分析乙腈。尽管根据理论计算，N-(苯并[d]噻唑-2-基)吡啶酰胺中可能有两种潜在的转换途径，要么通过吡啶，要么通过苯并噻唑部分，但实验结果显示与N-(苯并[d]噻唑-2-基)吡啶酰胺中的光动力学相同。 -(苯并[d]噻唑-2-基)异烟酰胺。这表明在两种化合物中，从酰胺 NH 到苯并噻唑氮的激发态质子转移是优选的。