作者:Xini Zhang、Michael Breslav、Jeffrey Grimm、Kailin Guan、Aihua Huang、Fuqiang Liu、Cynthia A. Maryanoff、David Palmer、Mitul Patel、Yun Qian、Charles Shaw、Kirk Sorgi、Stephen Stefanick、Dawei Xu
DOI:10.1021/jo026288n
日期:2002.12.1
The standard method for preparing carboxylic acid hydrazides is hydrazinolysis of esters in alcoholic solutions. However, when applied to alpha,beta-unsaturated esters, the main product typically is the pyrazolidinone resulting from an undesired Michael-type cyclization. Other alternative methodologies reported for direct preparation of hydrazides from acids are inefficient. We developed an efficient
制备羧酸酰肼的标准方法是在醇溶液中酯的肼解。然而,当应用于α,β-不饱和酯时,主要产物通常是由不希望的迈克尔型环化反应产生的吡唑烷酮。据报道,用于从酸直接制备酰肼的其他替代方法效率低下。我们开发了一种有效且通用的方法,包括预形成活化的酯和/或酰胺,然后与肼反应,以制备包括α,β-不饱和酸在内的酰肼。该方法在温和条件下以优异的产率和纯度得到所需的酰肼。