40849-04-5Relevant academic research and scientific papers
A novel route to 2,3-pyrazol-1(5H)-ones via palladium-catalyzed carbonylation of 1,2-diaza-1,3-butadienes
Boeckman Jr., Robert K.,Reed, Jessica E.,Ge, Ping
, p. 3651 - 3653 (2001)
Figure presented A novel Pd(0)-catalyzed carbonylation of both isolable 1,2-diaza-1,3-butadienes and those generated in situ by extrusion of SO2 and CO2 from heterocyclic precursors is described. The reaction proceeds at room temperature to 110°C under 1-2 atm of CO to afford 2,3-pyrazol-1(5H)-ones in good to excellent yields. The effect of catalyst structure and stability on the carbonylation reaction is evaluated.
A New Synthesis of 2-Pyrazolin-5-ones from the Condensation of C(α),N-Dilithiophenylhydrazones with Diethyl Carbonate
Wilson, Jana D.,Fulmer, Tammy D.,Dasher, Lisette P.,Beam, Charles F.
, p. 389 - 391 (2007/10/02)
C(α),N-Dilithiophenylhydrazones were prepared from phenylhydrazones in an excess of lithium diisopropylamide and condensed with diethyl carbonate followed dy an acid cyclization to give 2-pyrazolin-5-ones.
