Substitution at C-1, the Reducing Carbon

Formation of 2,3,4,6-tetra-O-acetyl-D-glucopyranose is obtained by treating bromoacetyl glucose in acetone containing silver carbonate [48,49] (reaction 4.48). 

The reaction of bromoacetyl glucose with lithium aluminum hydride in diethyl ether gives the substitution of hydrogen for the hemiacetal hydroxyl at C-1, and the formation of the nonreducing, 1,5-anhydro-D-glucitol [50,51] (reaction 4.49). The excess LiAlH is removed by the addition of ethyl acetate, which is reduced to ethanol. 

The 1-phosphate can be prepared by reaction of bromoacetyl glucose with silver phosphate in benzene or toluene. The anomeric form of the resulting product 

The reaction of bromoacetyl glucose and bromoacetyl galactose with sodium azide in DMF gives 68 and 75% yields, respectively, of the 1-P-azide [55] (reaction 4.53). The azide can be easily reduced by catalytic hydrogenation to give 1-glycosylamines. 

The direct substitution of peracetylated mono- and disaccharides by trimethyl-silyl azide, in the presence of a Lewis acid, produces the p-azide without the formation of the 1-bromide intermediate [56] (reaction 4.54). 

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