C‐C Bond Cleavage Studies in Bipyrazoles: A Convenient Synthesis of Pyrazolo‐5‐ols
作者:Shiv P. Singh、Rajesh Naithani、Ranjana Aggarwal、Om Prakash
DOI:10.1081/scc-200049811
日期:2005.3
treatment of 4‐acetoacetyl derivative (3) of the pyrazoles with hydrazines in ethanol/HCl furnished a variety of bipyrazoles (4). However, when the reaction was performed in sodium acetate/acetic acid/ethanol, different hydrazines gave different products. Under these conditions an unexpected C‐C bond cleavage was observed thus affording a convenient route for the formation of pyrazolo‐5‐ols (5 and 6)
摘要 在乙醇/HCl 中用肼处理吡唑的 4-乙酰乙酰基衍生物 (3) 得到了多种联吡唑 (4)。然而,当反应在乙酸钠/乙酸/乙醇中进行时,不同的肼得到不同的产物。在这些条件下,观察到了意想不到的 C-C 键断裂,从而为形成 pyrazolo-5-ols(5 和 6)提供了一条方便的途径。