Polymer-supported tin carbohydrate chemistry.
It was anticipated that stannylation of carbohydrates could be achieved using tin on a polymer-support. Such immobilization simplifies the purification of the carbohydrate because the toxic tin reagent can be removed by filtration. In this case an alkene linker (3-buten-1-ol) was added to chloromethylated 2% cross-linked polystyrene by etherification. Photochemical hydrostannylation with dibutyltinchlorohydride gave a polymer bound trialkyl tin chloride. The Sn-Cl could be hydrolysed with NaOH to yield a resin with terminal Sn-O bonds. Highly regioselective acylation of methyl alpha-D-mannopyranoside (alphaMeMan) to its 3-O-benzoyl derivative was achieved. Traces of the mono 6-O-benzoate and the 3,6-di-O-benzoate were also obtained. Methyl alpha-D-glucopyranoside was also selectively acylated to its 2-O-benzoate but this reaction gave a more complex mixture. The isolated yields (10-30% based on sugar) were disappointingly low. The yields were improved to about 60% with 5% cross-linked resin.
Whitfield
D M
DM
National Research Council, Ottawa, Ontario, Canada.
Ogawa
T
T
D000215:Acylation; D002241:Carbohydrates / Q000737:chemistry*; D009005:Monosaccharides / Q000737:chemistry; D011108:Polymers; D014001:Tin / Q000737:chemistry
D002241:Carbohydrates; D009005:Monosaccharides; D011108:Polymers; D014001:Tin