Studies on paraionic compounds. Anhydro-1-hydroxy-3-oxopyrazolo[1,2-a]pyrazolium hydroxides. Formation and stability of a novel series of 4n.pi. heterocyclic betaines
A Facile Synthesis of 1-Oxo-1<i>H</i>-pyrazolo[1,2-<i>a</i>]pyrazol-4-ium-3-olates
作者:Thomas Kappe、Carlo Kos
DOI:10.1055/s-1989-27341
日期:——
The thermal condensation at 200-300°C of pyrazoles 1a-c with substituted diethyl malonates 2a-c or triethyl methanetricarboxylate 2d yields the 1-oxo-1H-pyrazolo-[1,2-α]pyrazol-4-ium-3-olates 3a-h.