Protecting group and solvent control of stereo- and chemoselectivity in glucal 3-carbamate amidoglycosylation.
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.
Gupta
Ritu
R
Department of Chemistry, Barnard College, 3009 Broadway, New York, New York 10027, USA.
Sogi
Kimberly M
KM
Bernard
Sarah E
SE
Decatur
John D
JD
Rojas
Christian M
CM
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
D002219:Carbamates; D006595:Hexosamines; D023303:Oxazolidinones; C008322:mannosamine; D008358:Mannose; D002125:Calcium Gluconate