Standard Article

Fischer Phenylhydrazone and Osazone Synthesis

Published Online: 15 SEP 2010

DOI: 10.1002/9780470638859.conrr236

Comprehensive Organic Name Reactions and Reagents

Comprehensive Organic Name Reactions and Reagents

How to Cite

2010. Fischer Phenylhydrazone and Osazone Synthesis. Comprehensive Organic Name Reactions and Reagents. 236:1083–1087.

Publication History

  1. Published Online: 15 SEP 2010

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Abstract

The condensation between phenylhydrazine and a carbonyl compound (aldehyde or ketone) to form phenylhydrazone and the compounds condensed from carbohydrates and 2 eq of phenylhydrazine are generally known as osazones or specifically referred to as glycosazones. These reactions are known as Fischer phenylhydrazone and osazone synthesis. The glycosazones have been employed to elucidate the configuration of sugars. It has been found that the phenylhydrazones of aliphatic ketones and aldehydes rapidly tautomerize to the more stable azo isomers in solution and glycosazones of carbohydrates exist as chelated acyclic forms. This reaction has general application in the preparation of phenylhydrazones of carbonyl compounds and osazone derivatives of carbohydrates.

Keywords:

  • phenylhydrazone;
  • osazones;
  • acyclic osazone;
  • arylhydrazone