Pyridazin-1-ium-1-amine → 2-(4-ethoxy-phenyl)-pyrazolo[1,5-b]pyridazine-3-carboxylic Acid Methyl Ester

Participants

Reaction Steps

Diazabicyclo[5.4.0]undec-7-ene (1.47 ml, 2 eq) was added dropwise to a solution of methyl 3-(4-ethoxy-phenyl)-prop-2-ynoic acid (1.0 g) and 1-amino pyridazinium iodide2 (2.19 g) in acetonitrile (10 ml) under nitrogen and stirred for 5 h. Concentration and aqueous workup gave the title compound (1.2 g) as a sticky brown solid.

Provenance & Evidence