Pentafluorophenyl ester activation for the preparation of N,N′-diaroylhydrazines
摘要:
Procedures are reported for the preparation of N,N'-diaroylhydrazines using pentafluorophenyl (Pfp) ester activation of aryl carboxylic acids. Mild conditions which avoid intermediate protection of ring substituents, allows the synthesis of both symmetrical and unsymmetrical diaroylhydrazines in high yields. The recent discovery of potent HIV-1 integrase inhibition by N,N'-bis-salicylhydrazine (1) highlights the potential importance of this class of compounds. The stability of pre-activated Pfp ester intermediates and the facility with which N,N'-diaroylhydrazines can be synthesized using this procedure (stirring at room temperature in DMF) may make the method particularly attractive for synthesis of hydrazide libraries.
aminolysis reaction between various aryl esters and inert tertiaryamines by C–O and C–N bond activations has been developed for the selective synthesis of a broad scope of tertiary amides under neutral and mild conditions. The mechanism may undergo the two key steps of oxidativeaddition of acyl C–O bond in parent ester and C–N bond cleavage of tertiaryamine via an iminium-type intermediate.
Transesterification of (hetero)aryl esters with phenols by an Earth-abundant metal catalyst
作者:Jianxia Chen、E. Namila、Chaolumen Bai、Menghe Baiyin、Bao Agula、Yong-Sheng Bao
DOI:10.1039/c8ra04984j
日期:——
for the transesterification of aryl or heteroaryl esters with phenols which is a challenging and underdeveloped transformation. The simple conditions and the use of heterogeneous alkali metal catalyst make this protocol very environmentally friendly and practical. This reaction fills in the missing part in transesterification reaction of phenols and provides an efficient approach to aryl esters, which