Infrared Spectra of Sulfonamide Derivatives. II. Thiophene, Thiadiazole, and Isoxazole Derivatives
作者:Toyozo Uno、Katsunosuke Machida、Kazuhiko Hanai
DOI:10.1248/cpb.14.756
日期:——
Infrared spectra were applied to the studies on the amido-imido tautomerism of the sulfonamide derivatives containing the heterocyclic rings such as thiadiazole and isoxazole. 2-Phenylsulfonamidothiophene was used as a model compound of the amidoform. From the pattern of the spectral change on N-deuteration and the comparison with the corresponding carboxylic acid amides in the region 1650∼1500 cm-1, it was found that 2-sulfonamidothiadiazoles exist in the imido-form, while 3-and 5-sulfonamidoisoxazoles exist in the amido-form in the solid state. For most of the sulfonamides the SO2 symmetric stretching frequencies of the imido-form were found to be lower than those of the amido-form.
红外光谱被用于研究含有噻二唑和异噁唑等杂环的磺酰胺衍生物的氨基-酰亚胺同分异构体。2-Phenylsulfonamidothiophene 被用作氨基形式的模型化合物。从 N-氘化时的光谱变化规律,以及与相应的羧酸酰胺在 1650∼1500 cm-1 区域的比较中发现,2-磺酰胺基噻二唑在固态下以酰亚胺形式存在,而 3-和 5-磺酰胺基异噁唑则以氨基形式存在。对于大多数磺酰胺类化合物来说,亚氨基形式的 SO2 对称伸展频率低于酰胺形式的 SO2 对称伸展频率。