Multicomponent synthesis of pyridazine and pyridazinoquinazoline derivatives in the presence of catalysts such as magnesium oxide (MgO) and 12-tungstophosphoric acid (PW)

摘要

A series of 3-amino-2,5-dihydropyridazines and fused pyridazinoquinazolines have been prepared in a one-step procedure from three-component reactions of (arylhydrazono)-propan-2-ones, aldehydes and malononitrile or ethyl cyanoacetate in the presence of magnesium oxide (MgO) and 12-tungstophosphoric acid (PW) as highly effective heterogeneous catalysts. The salient features of these methods include high conversions, short reaction times, cleaner reaction profiles, and the use of inexpensive and readily available catalysts.