Preparation of<i>NH-</i>pyrazoleacetic acid anilides from trilithiated acetoacetanilide, select aromatic esters, and hydrazine
作者:Ellyn A. Smith、Chandra Potter、Zachary C. Kennedy、Andrew J. Puciaty、Amanda M. Acevedo-Jake、Stephen D. Hersey、Clyde R. Metz、William T. Pennington、Donald G. VanDerveer、Charles F. Beam
DOI:10.1002/jhet.285
日期:——
intermediate. This was followed by a regioselective Claisen-type condensation of the trilithiated intermediate with a variety of aromatic esters to afford new C-acylated intermediates, 3,5-diketopentane-carboxanilides, that were not isolated but immediately condensed-cyclized with hydrazine to afford the NH-pyrazoleacetanilides, 5-aryl-1H-pyrazole-3-acetanilides, before these C-acylated intermediates had an
用过量的二异丙基氨基锂将乙酰乙酰苯胺三锂化以形成反应性三阴离子型中间体。随后是三锂化中间体与多种芳香族酯的区域选择性Claisen型缩合反应,以提供新的C-酰化中间体3,5-二酮戊烷-甲酰苯胺,这些中间体未被分离,但立即与肼缩合环化,从而得到在这些C-酰化的中间体有机会重排为苯胺-吡喃酮,4-苯胺基-6-芳基-2 H-吡喃-2-酮之前,NH-吡唑乙酰苯胺,5-芳基-1 H-吡唑-3-乙酰苯胺。J.杂环化学.2010。