title: Synthesis and orthogonal functionalization of oxazolo[5',4':4,5]pyrano[2,3-b]pyridine by intra- and intermolecular Pd-catalyzed direct C-H bond heteroarylation.
abstract: The construction and subsequent orthogonal functionalization of a hitherto unknown oxazolo[5',4':4,5]pyrano[2,3-b]pyridine are reported. A palladium-catalyzed direct C-H bond functionalization methodology was used to build the tricyclic scaffold as well as to achieve the subsequent C-H bond functionalization at the C-2 position of the oxazole unit with various (hetero)aryl iodides. Remarkably, selective C-H construction and functionalization procedures preserve the chorine atom on the pyridine moiety offering a late-stage substitution site to progress drug design.
authors.affiliation: Normandie University, COBRA, UMR 6014 et FR 3038 University Rouen; INSA Rouen; CNRS, IRCOF 1 rue Tesnière 76821, Mont Saint Aignan Cedex, France. christophe.hoarau@insa-rouen.fr.
authors.forename: Laure
authors.initials: L
authors.lastname: Théveau
authors.forename: Cédric
authors.initials: C
authors.lastname: Schneider
authors.forename: Olivier
authors.initials: O
authors.lastname: Querolle
authors.forename: Lieven
authors.initials: L
authors.lastname: Meerpoel
authors.forename: Vincent
authors.initials: V
authors.lastname: Levacher
authors.forename: Christophe
authors.initials: C
authors.lastname: Hoarau