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A practical and efficient one-pot synthesis of 1,3,5-trisubstituted pyrazoles from α,β-enones and arylhydrazine hydrochlorides has been developed. The pyrazoles were formed via a tandem formation of the corresponding pyrazolines and an acid-catalyzed aerobic oxidation process.

Various pyrazolo[1,5‐a]quinolines were synthesized via the intramolecular Friedel‐Crafts reaction of 1‐aryl‐5‐styrylpyrazoles and the following base‐catalyzed aerobic oxidation process. The required 1‐aryl‐5‐styrylpyrazoles were readily prepared from the corresponding conjugated dienones and arylhydrazines in a one‐pot process.

The palladium-catalyzed, one-pot arylative cyclization of 3-(g,d-disubstituted)allylidene-2oxindoles afforded spirodihydronaphthalene-2-oxindole frameworks via an oxidative Heck arylation (Fujiwara-Moritani reaction), an allylic palladium migration, and an aryl C À H bond functionalization/ arylation cascade of reactions. This is a first example of the palladium-catalyzed oxidative arylation and an aryl C À H bond functionalization/arylation cascade reaction which involves an electrophilic arylative quenching of a p-allylpalladium intermediate and a regio-controlled aryl C À H bond activation assisted by a weak palladium-arene interaction.

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