Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5224114 | Tetrahedron | 2010 | 9 Pages |
Suzuki-Miyaura cross-coupling processes on N-pyridinium bromoazinyl aminides allow access to 3,5-disubstituted N-alkyl-2-aminopyridines. The synthetic pathway involves a regioselective bromination of pyridinium N-(pyridin-2-yl)aminide and a subsequent reaction with boronic acids to afford monosubstituted aminides in good yields. An additional bromination in the 5-position of the pyridine ring followed by a coupling reaction gives pyridinium N-(3,5-diarylpyridin-2-yl)aminides. Finally, a regioselective alkylation on the exo-nitrogen and reduction of the N-N bond yields highly substituted 2-aminopyridines.
Graphical abstractThe N-(pyridin-2-yl)pyridinium aminide allows, through two regioselective brominations followed by Suzuki-Miyaura cross-coupling processes together with a selective alkylation on the exo-nitrogen and reduction of the N-N bond, the access to 3,5-disubstituted N-alkyl-2-aminopyridines.Download full-size image