Mild synthesis of 2,3,5,6-tetrafluoropyridine ethers and their reactivity toward imidazole and pyrazole.

• Nucleophilic aromatic substitution (SNAr) of pentafluoropyridine with aliphatic alcohols and phenols afforded a series of six 4-substituted 2,3,5,6-tetrafluoropyridine (TFP) hetero ethers. • 4-substituted TFP hetero ethers served as intermediates for the preparation of terepyridine scaffolds 3,5-difluoro-2,6-bis(pyrazolyl)pyridine and 4-(hexyloxy)−2,3,5,6-tetra(1H -pyrazol-1-yl)pyridine. • The highly organic soluble, low vapor pressure TFP hetero ethers should garner interest for weakly binding to heterogeneous surfaces and influence bulk properties by nature of the aliphatic/aromatic substitution. • 3,5-Difluoro-2,6-bis(pyrazolyl)pyridine and 4-(hexyloxy)−2,3,5,6-tetra(1H -pyrazol-1-yl)pyridine compounds could serve as strong metal binding as ligands or scaffolds within larger macromolecular systems. A series of six, 4-substituted 2,3,5,6-tetrafluoropyridine (TFP) hetero ethers have been synthesized via regio-selective, nucleophilic aromatic substitution (SNAr) of pentafluoropyridine with aliphatic alcohols and phenols. Furthermore, the hexyloxy modified TFP substrate also served as a synthetic intermediate for the preparation of 3,5-difluoro-4-(hexyloxy)-2,6-di(1H -imidazol-1-yl)pyridine, as well as 4-(hexyloxy)-2,3,5,6-tetra(1H -pyrazol-1-yl)pyridine, which offers a terpyridine scaffold. This work outlines their synthetic methodology in addition to detailing the TFP intermediates' unexpected reactivity with imidazole and pyrazole nucleophiles [Display omitted] [ABSTRACT FROM AUTHOR]