On the synthesis of 3-cyano-6-hydroxy-4-methyl-2-pyridone at room temperature

Abstract

Milling of cyanoacetamide and acetoacetic ester as reactants, in the presence of KOH as the catalyst and ethanol as a viscous control agent (VCA) was performed in a planetary ball mill with the goal of investigating the effect of mechanochemical treatment for the synthesis of 3-cyano-6hydroxy-4-methyl-2-pyridone at room temperature. The mechanochemical synthesis was performed under various milling parameters, i.e. milling time up to 4 h, number and size of balls, angular velocity as well as molar ratio of reactants and the amount of catalyst. The obtained product was characterized by m.p., UV, IR and NMR data. It was fond that the dominant process parameter is the milling time while others are of less importance. The highest isolated yield after milling was up to 56%. The combination of milling and aging increase yield over 60%.

Mlevenje cijanoacetoamida (2) i acetsirćetnog estra (1) kao reaktanata, u prisustvu KOH kao katalizatora i etanola kao agensa kojim se kontroliše viskoznost, izvedeno je u planetarnom mlinu radi ispitivanja mogućnosti mehanohemijske sinteze 3-cijano-6-hidroksi-4-metil-2-piridona (3) na sobnoj temperaturi. Mehanohemijski tretman je izveden sa različitim parametrima mlevenja: vremenom mlevenja do 4 h, različitom veličinom i brojem kuglica, različitom brzinom obrtanja, kao i različitim molarnim odnosom reaktanata i katalizatora. Dobijeni proizvod je okarakterisan određivanjem temperature topljenja, UV, IR i NMR analizama. Nađeno je da je dominantni procesni parametar vreme mlevenja, dok su ostali od manjeg uticaja. Najveći prinos izolovanog proizvoda je oko 56%, dok se naknadnim "odležavanjem" prinos povećava preko 60%.