Midha K K, Awang D V, McGilveray I J
Biomed Mass Spectrom. 1976 Jun;3(3):100-9. doi: 10.1002/bms.1200030303.
Gas chromatographic analysis of the products of reaction of diazomethane with tolbutamide and chlorpropamide indicates the formation of three compounds in both cases. As expected, N-methylation (at sulfonamide nitrogen) is the predominant reaction; minor amounts of O-methylated product are also observed. The third product in both cases is the N-methylsulfonamide formed by decomposition of the N-methylated sulfonylurea during gas chromatography. Electron impact and chemulfonylurea during gas chromatography. Electron impact and chemical ionization mass spectrometric analysis, as well as 1H nuclear magnetic resonance examination of samples collected from gas chromatography, confirm the structural assignments. Additionally, proton magnetic resonance analysis of the crude reaction products established that N-methylsulfonamides are not formed in the course of the diazomethane reaction and that the O-methylated derivatives are true products of the reaction. The use of a paramagnetic shift reagent allowed direct estimation of the ratios of N- to O-methylation, and the demonstration that these ratios are not vitiated during gas chromatographic analysis.
对重氮甲烷与甲苯磺丁脲和氯磺丙脲反应产物进行气相色谱分析表明，两种情况下均生成了三种化合物。正如预期的那样，N-甲基化（在磺酰胺氮处）是主要反应；也观察到少量的O-甲基化产物。两种情况下的第三种产物是在气相色谱过程中由N-甲基化磺酰脲分解形成的N-甲基磺酰胺。电子轰击和化学电离质谱分析，以及对从气相色谱收集的样品进行的1H核磁共振检查，证实了结构归属。此外，对粗反应产物的质子磁共振分析表明，在重氮甲烷反应过程中不会形成N-甲基磺酰胺，且O-甲基化衍生物是该反应的真实产物。使用顺磁位移试剂可以直接估算N-甲基化与O-甲基化的比例，并证明这些比例在气相色谱分析过程中不会受到影响。
