Transformation of Nitriles and Heteroatom Nucleophiles to Carboxylic Acid Derivative s

2 Transformation of Nitriles and Heteroatom Nucleophiles to Carboxylic Acid (Derivative)s 

Side Note 7.2. Chemistry of Imidic Acid Ester Hydrochlorides Preparation of Orthoesters and Amidines 

In the first step of the Kiliani-Fischer synthesis, HCN adds to the C=0 double bond of the tetrahydroxy aldehyde, which is in equilibrium with the predominant hemiacetal form of ara- 

Imidic acid ester hydrochlorides (F)—to be prepared from nitriles, hydrogen chloride (gas) and methanol acc. to Fig. 7.13—, their trans-formability into orthoester (A) or amidine (I) and the corresponding reaction mechanisms. 

Kiliani-Fischer method for the homologation of aldoses to give the dia-stereomeric mixture of the next higher aldose. Three-step syntheses of this kind (here D-arabinose — D-glucose + D-mannose) played a central role when about a hundred years ago Emil Fischer managed to determine the configuration of aldoses by chemical ( ) methods. 

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