N.M.R. evidence for the acyclic structure of some sugar phenylhydrazones: a confirmation of the formazan test.

✍ Scribed by L. Mester; G. Vass

• Book ID: 104223008
• Publisher: Elsevier Science
• Year: 1968
• Tongue: French
• Weight: 154 KB
• Volume: 9
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)89819-6

✦ Synopsis

Two methods rendered good service in the elucidation of the acyclic aldehvdo-structure of some sugar phenylhydrazones: the acetylation method (1,2) and the formazan reaction (3,4,5). The results obtained by these methods were confirmed by U.V. spectral data ( 6) and also by polarographic investigations (7).

Recently Blair and Roberts (8) called in question the usefulness of both methods in view of their investigations , especially of the p-bromophenylhydrazone of L-arabinose, by infrared spectroscopy. The i.r. data confirmed the cyclic structure of this compound in solid state, proposed earlier on the basis of X-ray studies (9). However, they also found a positive formazan test for this compound, indicating the presence of the acyclic aldehvdo-structure. Because of this apparent contradiction Blair and Roberts rejected the evidence furnished by the formazan method.