Base-Mediated Syntheses of New 6,6′-Di(polyfluoroalkoxy)-2,2′-Bipyridines with 100% Regioselectivity

Abstract

Reactions of N,N-difluoro-2,2′-bipyridinium bis(tetrafluoroborate) (MEC-31) (1) with fluorinated alcohols R_fOH [R_f = CF₃CH₂, CH₂FCH₂, CF₃CF₂CH₂, CHF₂CF₂CH₂, (CF₃)₂CH] 2a-e, in the presence of a base at 70 °C without solvent, gave good yields of 6,6′-di(polyfluoroalkoxy)-2,2′-bipyridines 3a-e with 100% regioselectivity. Triethylamine with 1, produced 6,6′-difluoro-2,2-bipyridine (4).

Key words

alcohols - fluorine - pyridines - regioselectivity

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