Dearomative, aminocatalytic formal normal-electron-demand aza-Diels–Alder cycloaddition in the synthesis of tetrahydrofuropyridines

Abstract

In the manuscript the application of dearomative formal normal-electron-demand aza-Diels–Alder cycloaddition in the synthesis of tetrahydrofuropyridines is described. The developed approach utilizes aminocatalytic activation of 2-alkyl-3-furfurals that proceeds via formation of the dearomatized dienamine intermediate. Initially obtained cycloadducts have been subjected to subsequent transformations providing access to tetrahydrofuropyridines or functionalized cinnamates. The mechanism of the process has been confirmed by DFT calculations.