Radikalreaktionen an N-Heterocyclen. XI [1] Reaktionen von 3-Methyl-pyrazolin-5-onen mit Phenoxyl-Radikalen
作者:Manfred Schulz、Michael Meske
DOI:10.1002/prac.19933350706
日期:——
Pyrazolin-5-ones (3a-4) were oxidized with 2,4,6-trisubstituted phenoxy radicals (2a-d) to the corresponding radicals (4a-i), which dimerised or combined with phenoxy radical (2a) depending on the R1- and R4-substituents in (3). In the case of 3-methyl-1-phenyl-pyrazolin-5-one (3f) the primary radical combination products were not found, but the corresponding quinone methide (17) and the o-phenol derivative (18) were isolated. Products and yields have been investigated as a function of mol ratio substrate: oxidant and solvent. The radical combination products (7-10) could de-tertbutylated in the presence of aluminium chloride or in the presence of trifluoroarcetic acid, forming heterocyclic substituted phenols (21) and (22).
Accidental synthesis of a trimer of pyrazolone and comparison of its antioxidant activity: an investigatory report
作者:Arti Jain、Sushma Yadav、Priti Malhotra
DOI:10.1007/s12039-021-01943-0
日期:2021.9
Untargeted synthesis leading to the formation of a significant product is a common practice and has been successfully achieved after holistic characterization of the accidentally formed molecule of the trimer of pyrazolone. Its significance was further explored in the pharmaceutical field emphasizing the need for the synthesis and validating the newly established pathways for its synthesis. It was known