Question

Glucose, when heated with $C{H}_{3}OH$, in presence of dry $HCl$ gas, $\alpha -$methyl glucosides and $\beta -$methyl glucosides are formed. This is because it contains:

• A. an aldehyde group
• B. $C{H}_{2}OH$ group
• C. a ring structure
• D. five hydroxy groups

Answer 1

The correct option is C a ring structure

Glucose reacts with methanol, in presence of dry HCl, to form alpha and beta methyl glycosides.
$C_6{H}_{12}{O}_6+C{H}_{3}OH\to \underset{X}{\alpha -C_6{H}_{11}{O}_{6}C{H}_3}+\underset{Y}{\beta -C_6{H}_{11}{O}_{6}C{H}_3}$
Formation of alpha and beta methyl glycosides is due to the ring structure of glucose, as the methyl alcohol can attack the anomeric carbon in 2 ways, leading to these two configurations.