Interconversion of 3-Acylaminobenzisoxazoles and 3-(2-Hydroxyphenyl)-1,2,4-oxadiazoles
作者:Kálmán Harsányi
DOI:10.1002/jhet.5570100613
日期:1973.12
Interconversion of 3-(2-hydroxyphenyl)-1,2,4-oxadiazoles (1) and 3-acylaminobenzisoxazoles (2) was observed in the presence of base carboxylate anion, triethylamine, alkali hydroxide, alcoholate. With proton transferring reagents (carboxylate, triethylamine) the equilibrium 1⇌2 is dependent on the substituent R; with anionic reagents (hydroxy anion, ethoxyl anion) the less basic anion of 1 is preferred
在碱式羧酸根阴离子,三乙胺,碱金属氢氧化物,醇盐存在下,观察到3-(2-羟苯基)-1,2,4-恶二唑(1)和3-酰基氨基苯并恶唑(2)的相互转化。对于质子转移试剂(羧酸盐,三乙胺),平衡1⇌2取决于取代基R;在使用阴离子试剂(羟基阴离子,乙氧基阴离子)时,优选碱性较低的1。醇作用使该阴离子进一步转化,醇加合物阴离子(6)既要水解又要醇解(7),从而生成3-氨基-苯并恶唑(3)。