title: Protecting group and solvent control of stereo- and chemoselectivity in glucal 3-carbamate amidoglycosylation.
abstract: In the Rh(2)(OAc)(4)-catalyzed amidoglycosylation of glucal 3-carbamates, anomeric stereoselectivity and the extent of competing C3-H oxidation depend on the 4O and 6O protecting groups. Acyclic protection permits high alpha-anomer selectivity with further improvement in less polar solvents, while electron-withdrawing protecting groups limit C3-oxidized byproducts. Stereocontrol and bifurcation between alkene insertion and C3-H oxidation reflect an interplay of conformational, stereoelectronic, and inductive factors.
authors.affiliation: Department of Chemistry, Barnard College, 3009 Broadway, New York, New York 10027, USA.
authors.forename: Ritu
authors.initials: R
authors.lastname: Gupta
authors.forename: Kimberly M
authors.initials: KM
authors.lastname: Sogi
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Bernard
authors.forename: John D
authors.initials: JD
authors.lastname: Decatur
authors.forename: Christian M
authors.initials: CM
authors.lastname: Rojas
mesh_terms: D002125:Calcium Gluconate / Q000737:chemistry*; D002219:Carbamates / Q000737:chemistry*; D002384:Catalysis; D020650:Combinatorial Chemistry Techniques; D006031:Glycosylation; D006595:Hexosamines / Q000138:chemical synthesis* / Q000737:chemistry; D008358:Mannose / Q000031:analogs & derivatives / Q000138:chemical synthesis*; D015394:Molecular Structure; D023303:Oxazolidinones / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D002219:Carbamates; D006595:Hexosamines; D023303:Oxazolidinones; C008322:mannosamine; D008358:Mannose; D002125:Calcium Gluconate