A contribution to the chemistry of pyrazole-type dianhydrophenylosazones

✍ Scribed by László Somogyi

• Publisher: Elsevier Science
• Year: 1985
• Tongue: English
• Weight: 449 KB
• Volume: 144
• Category: Article
• ISSN: 0008-6215
• DOI: 10.1016/0008-6215(85)85007-2

✦ Synopsis

Tetra-0-acetyl-o-lyxo-hexosulose 1-acetylphenylhydrazone 2-phenylhydrazone (10) was transformed into 5-(D-glycero-1,2-diacetoxyethyl)-3-formyl-lphenylpyrazole acetylphenylhydrazone (~-4, n = 3) in boiling acetic anhydride containing anhydrous sodium acetate. Racemic 3,4,6-tri-O-acetyl-5-deoxyhex-4-enos-2-ulose 1-acetylphenylhydrazone 2-phenylhydrazone (11) was isolated as an intermediate in the reaction performed in the absence of sodium acetate. The cyclisation of 11, via allylic rearrangement, into DL-4 (n = 3) and 5-(IX-glycero-1,2-dihydroxyethyl)-3-formyl-l-phenylpyrazole acetylphenylhydrazone (DL-3, n = 3) in acidic, neutral, and basic media is described.