A synthesis of 1-substituted-3-hydroxy-4,5-cycloalkylpyrazoles

✍ Scribed by Neville Finch; Heinz W. Gschwend

• Publisher: Elsevier Science
• Year: 1969
• Tongue: French
• Weight: 105 KB
• Volume: 10
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)87973-9

✦ Synopsis

The preparation of 2-aryl(or alkyl)-3-hydroxytetrahydroindazoles is well known.

As described nearly seventy years ago (i~ condensation of ethyl 2-oxo-cyclohexanecarboxylate with phenylhydrazine leads exclusively to 2-phenyl-3-hydroxytetrahydroindazole I.

A general synthesis of the isomeric l-aryl(or alkyl)-3-hydroxytetrahydroindazoles IV (n = 2) has, to our knowledge, not been described. We now report such a process.