What happens when D-glucose is treated with the following reagents?
(a) Br$_2$ water
(b) HCN
(a) Br$_2$ water
(b) HCN
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Solution and Explanation
(a) Br2 water
When D-glucose is treated with bromine water (Br2 in H2O), the aldehyde (-CHO) group at C-1 is selectively oxidized to a carboxylic acid (-COOH), forming D-gluconic acid.
(b) HCN
When D-glucose is treated with hydrogen cyanide (HCN), the -CHO (aldehyde) group at C-1 reacts with HCN, forming a cyanohydrin (-C(OH)(CN)). This reaction increases the carbon chain by one, leading to the formation of a cyanohydrin derivative.
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