I. O. Mastronardi, S. M. Flematti, J. O. Deferrari
Dec 1, 1966
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0
Influential Citations
72
Citations
Quality indicators
Journal
Carbohydrate Research
Abstract
Abstract Various tetra- O -acetyl- D -hexopyranoses were known to undergo acetyl migration upon methylation with Purdie's reagents; thus, 1,2,3,4-tetra- O -acetyl-β- D -glucopyranose, 1,2,3,6-tetra- O -acetyl-β- D -glucopyranose, and 1,3,4,6-tetra- O -acetyl-β- D -glucopyranose and its α anomer are converted into methyl 2,3,4,6-tetra- O -acetyl-β- D -glucopyranoside when methylated with methyl iodide and silver oxide. It is now found that, when each of the above compounds is treated with diazomethane-boron trifluoride etherate, the methylated product is produced in high yield, with the methyl ether group in the expected position. Under the same conditions, 1,3,4,6-tetra- O -α- D -galactopyranose is converted into the 2-methyl ether without the acetyl migration which had been observed when the tetra- O -acetyl- D -galactopyranose was methylated with Purdie's reagents. The tetra- O -acetyl- O -methyl- D -hexopyranoses were then transformed by deacetylation into the following mono- O -methylhexoses: 2- O -methyl-β- D -glucose, 4- O -methyl- D -glucose, 6- O -methyl-α- D -glucose, and 2- O -methyl-β- D -galactose.