| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1315116 | Journal of Fluorine Chemistry | 2010 | 5 Pages |
The regiochemistry of nucleophilic substitution of 4-phenylsulfonyl tetrafluoropyridine with unequal bidentate nucleophiles was investigated. The first nucleophilic substitution occurs at the 2-position of the pyridine ring by nitrogen nucleophile site (secondary or primary amine) followed by intermolecular ring closure at the geometrically accessible 3-position of the pyridine ring (by S, O and N nucleophiles). From this investigation, difluorinated tetrahydropyrido[3,4-b][1,4]oxazine, thiazine and pyrazine scaffolds were synthesized very readily by a one-pot annelation reaction of 4-phenylsulfonyl tetrafluoropyridine with appropriate unequal bidentate nucleophiles.
Graphical abstractReaction of 4-phenylsulfonyl tetrafluoropyridine with unequal bidentate nucleophiles in the presence of sodium bicarbonate and acetonitrile as solvent give difluorinated tetrahydropyrido[3,4-b][1,4]oxazine, thiazine and pyrazine systems.Figure optionsDownload full-size imageDownload as PowerPoint slide
