Synthesis of 1,2,4-Triazole and 1,3,4-Thiadiazole Derivatives from Methyl 2-Methyldithiocarbazate and Heterocumulenes
作者:Pedro Molina、Alberto Tárraga、Arturo Espinosa
DOI:10.1055/s-1989-27431
日期:——
Methyl 2-methyldithiocarbazate 1, reacts with diarylcarbodiimides to give 4-aryl-3-arylamino-1-methyl-5-thioxo-4,5-dihydro-1H-1,2,4-triazoles 3. Compound 1 also reacts with isothiocyanates to give the corresponding 5-arylamino-3-methyl-2-thioxo-2,3-dihydro-1,3,4-thiadiazoles 6. The reaction of the 3-triphenylphosphoranylidene derivative of 1 with aromatic isocyanates leads to the mesoionic anhydro-2-arylamino-4-methyl-5 -methylthio-1,3,4-thiadiazolium hydroxides 10. Methyl 3-aminocarbonyl-2 -methyldithiocarbazates 11, available from 1 and isocyanates, undergo ring closure on reaction with thionyl chloride to give either 1,3,4-thiadiazole derivatives 12 or 1,2,4-triazole derivatives 13.
甲基2-甲基二硫代卡巴胺1与二芳基碳二亚胺反应生成4-芳基-3-芳胺基-1-甲基-5-硫酮-4,5-二氢-1H-1,2,4-三唑3。化合物1还能与异硫氰酸酯反应,生成相应的5-芳胺基-3-甲基-2-硫酮-2,3-二氢-1,3,4-噻二唑6。1的3-三苯基膦亚胺衍生物与芳香异氰酸酯反应,生成中离子安缩-2-芳胺基-4-甲基-5-甲硫基-1,3,4-噻二唑锍氢氧化物10。由1和异氰酸酯可得的甲基3-氨基羰基-2-甲基二硫代卡巴胺11在氯磺酰反应下发生环化,生成1,3,4-噻二唑衍生物12或1,2,4-三唑衍生物13。