Reactions of 5-substituted 3-alkyl- and 3-aryl-isoxazoles with tetrasulfur tetranitride antimony pentachloride complex (S4N4·SbCl5): complete regioselective formation of 4-substituted 3-acyl- and 3-aroyl-1,2,5-thiadiazoles and their mechanism of formation
作者:Kil-Joong Kim、Kyongtae Kim
DOI:10.1039/a802408a
日期:——
The reactions of 3-alkyl- 5a–f, 3-aryl- 5g–m, 3-acylamido- 5n,p, 3-benzamido- 5o and 3-arylamino- 5q -5-alkyl- and -5-aryl-isoxazoles with tetrasulfur tetranitride antimony pentachloride complex (S4N4·SbCl5) in toluene at 90 °C to reflux temperature give 3-acyl- 6a–c, e, n–q and 3-aroyl-4-substituted-1,2,5-thiadiazoles 6d, f–m in 13 to 61% yields as single isomers. The same reactions of 3,4-dimethyl-
3-烷基-5a-f,3-芳基-5g-m,3-酰基酰胺基-5n,p,3-苯甲酰胺基-5o和3-芳基氨基-5q -5-烷基-和-5-芳基-异恶唑的反应四氮化四锑五氯化锑(S 4 N 4 ·SbCl 5)在90°C的甲苯中至回流温度,得到13-61%的3-酰基-6a-c,e,n-q和3-芳酰基-4-取代的1,2,5-噻二唑6d,f-m产生为单一异构体。3,4-二甲基-5s,5v,4-乙基-3-甲基-5t -5-烷基-和/或5-芳基-异恶唑在相同条件下的相同反应得到3-(1-乙酰基-1-氯乙基)-8a,3-(1-苯甲酰基-1-氯丙基)-8b,3-(1-苯甲酰基-1-氯乙基)-8d或3-(1-苯甲酰基-1-氯乙基)-4-甲基- 1,2,5-噻二唑8c是一种新型的1,2,5-噻二唑衍生物。另外,在相同条件下,与具有供电子取代基例如甲基,4-甲基苯基和4-甲氧基苯基的5-芳基-4-溴异恶唑(5,w,y,z)在相同条件下反应,得到3-芳酰基。