2,5-DIARYL-1,3,4-OXADIAZOLE HYDROXYESTER, HYDROXYACID AND ACETOXYACID AND SYNTHESIS THEREOF

摘要

PURPOSE: To provide novel 2,5-diaryl-1,3,4-oxadiazole hydroxyester, hydroxyacid or acetoxyacid obtained from novel diaromatic dihydrazide, which is useful as a monomer useful in hat tautomeric polymer synthesis. ;CONSTITUTION: 2,5-diaryl-1,3,4-oxadiazole hydroxyester, hydroxyacid and acetoxyacid of formula I (R₁ is hydroxy or acetyl; R₂ is carboxyl; preferably, R₁ and R₂ each occupies the 3, 3' or 4, 4' position simultaneously), e.g. 2-(4- hydroxyphenyl)-5-(4-methoxycarbonylphenyl)-1,3,4-oxadiazole are provided. The compound of the formula I is obtained by subjecting p, o- or m-hydroxybenzoic acid to condensation with an acid chloride of formula II to obtain a novel diaromatic dihydrazide of formula III, which is subsequently cyclized using thionyl chloride to obtain a diaryl oxadiazole hydroxyester, which is saponified or acetylated if required.;COPYRIGHT: (C)1994,JPO