Facile Synthesis of Dihydropyridones from Nitriles

Abstract

A short and efficient procedure for the synthesis of N-unsubstituted 2-aryl-2,3-dihydro-4(1H)-pyridinones from Danishefsky’s diene and triethylborylimines is described. Trialkylborylimines were prepared in situ from nitriles and trialkylborohydrides. The method is compatible only with aromatic nitriles. 6-Substituted 5,6-dihydro-4-ethoxy-2(1H)-pyridinones have been prepared analogously, albeit in low yield, from Brassard’s diene.

Key words

Diels-Alder reaction - imines - nitriles - dihydropyridones - N-borylimines

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