The structure of L-(+)-threose and L-(+)-erythrose is to be represented and the aldotriose, which must be used for the preparation of the above-mentioned compounds in the Kiliani-Fischer synthesis, is to be determined. Concept Introduction: ▸ The Kiliani-Fischer reaction is used for increasing the number of carbon atoms of an aldose molecule, as a result of the formation of the epimeric aldonic acid. ▸ It is an effective and economic process for the synthesis of monosaccharides by the process of hydrolysis of a cyanohydrin . ▸ Furthermore, it can also be used for the production of epimers of higher aldoses from a lower aldose, that is, a single aldose produces a mixture of two diastereomeric sugars called epimers .

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Chapter 22, Problem 13PP

Interpretation Introduction

Interpretation:

The structure of L-(+)-threose and L-(+)-erythrose is to be represented and the aldotriose, which must be used for the preparation of the above-mentioned compounds in the Kiliani-Fischer synthesis, is to be determined.

Concept Introduction:

▸ The Kiliani-Fischer reaction is used for increasing the number of carbon atoms of an aldose molecule, as a result of the formation of the epimeric aldonic acid.

▸ It is an effective and economic process for the synthesis of monosaccharides by the process of hydrolysis of a cyanohydrin.

▸ Furthermore, it can also be used for the production of epimers of higher aldoses from a lower aldose, that is, a single aldose produces a mixture of two diastereomeric sugars called epimers.

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