Some new experimental results are described on the acid catalysed reaction of the 4-Pyrazoline-3-on (1a) with aromatic aldehydes leading to the cationic derivatives 4 and 5. 4-Pyrazoline-3-on-lithium (1b), synthesised for the first time, gives in good yield with 4-dimethylaminobenzaldehyde under mild condition the cyanine 2b and with benzophenone the pyrazolyl-diphenylmethane dye 8.
|Translated title of the contribution||On the reaction of phenazone and lithiated phenazone with aryl-carbonyl derivatives|
|Number of pages||7|
|Journal||Monatshefte für Chemie Chemical Monthly|
|State||Published - Feb 1 1984|
- Pyrazolyl cyanine dyes