Question

Show the products arising from the reactions of the sugar Y below to indicate whether the products are chiral or achiral. Provide chemical names for both the Y sugar and ALL OF THE PRODUCTS

3, es points) Show the produces arising from the reactions of the sag v below and indisats chiral or achital. Provide chemical names for both the sugar Y and NaBH4 Briz. Hzo HO OH H2OH PhNHNH2 dilute HNO3 (excess) 1) NaCN, HCI 2) H2, Pd Baso4 3) H30*

Answer 1

The sugar Y is D-xylose.

Part a: Oxidation with bromine water

CHO COOH 2 H 11,1) 11 Oll 6 HOH HO -H 2 CH2OH CH,OH

The sugar is oxidized into a carboxylic acid. The product formed is xylonic acid. This is a chiral sugar.

Part b: Reduction

CHO CH,OH H OH NaBH HOH HOH CH,OH CH,OH

The aldehyde is reduced to an alcohol. The product is achiral and is named as xylitol.

Part c: Oxidation by nitric acid

CHO COOH dil. HNO, OH HOH CH OH COOH

The primary alcohol and aldehyde both are oxidized to carboxylic acid groups. The chirality is lost. This is named as xylaric acid.

Part d: Osazone formation

CHO C=N-NHPh HOH CH,OH CH OH

C1 and C2 reacts to form an osazone. The sugar is chiral.