Heterocyclization reactions of azinoisocyanates. Synthesis of 2<i>H</i>-1,2,4-triazol-3(4<i>H</i>)-one derivatives
作者:Kee-Jung Lee、Jin Lyang Kim、Mun Ki Hong、Jung Yong Lee
DOI:10.1002/jhet.5570360520
日期:1999.9
The reaction of 1-aminoethylidenehydrazones 9 with di-tert-butyl dicarbonate and 4-dimethylaminopyridine led to the corresponding azinoisocyanates 10, which underwent thermal rearrangement under the reaction conditions to give 4-(tert-butoxycarbonyl)-5-methyl-2H-1,2,4-triazol-3(4H)-ones 14. However, amidrazone 17 gave 2-(2-tert-butoxycarbonyloxy-2-phenyl)ethyl-4-(tert-butoxycarbonyl)-5-methyl-2H-1
1-aminoethylidenehydrazones的反应9与二-叔丁基酯和4二甲基氨基吡啶导致相应azinoisocyanates 10,其在反应条件下进行热重排,得到4-(叔丁氧基羰基)-5-甲基-2- ħ - 1,2,4-三唑-3(4 H)-ones 14。然而,胺酮17给出了2-(2-叔丁氧基羰基氧基-2-苯基)乙基-4-(叔丁氧基羰基)-5-甲基-2 H -1,2,4-三唑-3(4 H)- 22和N-叠氮基亚胺基氨基甲酸酯在类似条件下为18。