Emil Fischers Discovery and Application of the Synthesis

In 1889 Fischer discovered that the lactones of the acids of the sugar group can be reduced by sodium amalgam to yield the corresponding carbonyl compound, an aldose. The addition of this reaction to the cyanohydrin procedure of Kiliani made possible the first synthesis of 

Using the van t Hoff-Le Bel theory as a guide, Fischer extended his cyanohydrin syntheses from the work with xylose and arabinose to researches on all the other aldoses that were available in quantity at that time the list consisted of glucose, mannose, galactose, rhamnose, lactose and maltose. The experimental results with the disaccharides 

The writer makes the following comments. The mannooctonic lactone that Fischer, Passmore and Hagenbach had in hand was certainly D-manno-L-monno-octonic lactone it was later made by Peirce (ref. 23, p. 8) and also by workers in the writer s laboratory in connection with the research of ref. 55 (p. 18). Our data, not published before, are m. p. 169-172°, and in 

Here the synthesis led to an o-galaheptose (amorphous) and from it a galaoctose (crystalline) was prepared. Many years later the a-gala-heptose was crystallized. The 8-galaheptose crystallized in Fischer s research, and the epimeric character of the two galaheptoses was made highly probable by his interconversion of their aldonic acids on heating with aqueous pyridine. 

List of Configurations and Systematic Names for the Aldoheptoses and Heptitols from n-Glucose, o-Mannose and o-Galactose 

They were recrystallized from 200 cc. 96% alcohol, as small needles, m. p. 177-178° and +42°. The m. p. and magnitude of rotation agreed 

of nononic phenylhydrazide was obtained the lactone from every experiment except the first, always melted with decomposition at some point between 192° and 202° the rotations of two samples are recorded +55° 

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