Microwave-Assisted Synthesis of Polysubstituted Pyridazines

Abstract

3,4,6-Trisubstituted pyridazines are prepared through a microwave-assisted cyclocondensation of differently substituted 1,4-diketones and hydrazine in the presence of DDQ. The 1,4-di­ketones can be easily prepared through a functional homologation of commercially available β-keto esters providing a very rapid entry to these family of pharmaceutically important compounds.

Key words

pyridazines - microwaves - cyclocondensation - combinatorial chemistry

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9

A monomode Discover system from CEM was employed using a sealed vial with a maximun pressure internal control of 250 psi.