The Palladium-Catalyzed Glycosylation of Halotropones

Org Lett. 2023 Jan 20;25(2):384-388. doi: 10.1021/acs.orglett.2c04099. Epub 2023 Jan 6.

Abstract

A range of mono- and disaccharides, including glucose derivative 10, has been cleanly coupled, in the presence of a Pd catalyst, with various halogenated and structurally distinctive tropones, including "parent" compound 11, to afford the corresponding α- and β-anomeric forms of the tropolone glycosides, e.g., 12 and 13, respectively. Varying the ligand used influences the anomer distribution significantly and such that either the α- or β-form predominates. Notable chemo- and regioselectivities are observed when dihalogenated troponoids are employed as coupling partners.