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An efficient and diastereoselective [2+1] annulation of arylidenepyrazolones with bromides has been developed that relies on in situ formation of sulfur ylide via a direct sulfide‐catalyzed process. A variety of spirocyclopropanyl pyrazolones were achieved in good to excellent yields (up to 93% yield) with high diastereoselectives (up to 20 : 1 dr). Meanwhile, several spirocyclopropanyl compounds were also prepared from corresponding enones. This catalytic strategy exhibits good functional group tolerance, gram‐scale capacity and broad substrate scope, and provides various spirocyclopropanyl derivatives. [ABSTRACT FROM AUTHOR]

An efficient method for the synthesis of 3‐trifluoromethylquinoxalin‐2(1H)‐ones by a direct trifluoromethylation of quinoxalin‐2(1H)‐one derivatives has been developed under transition‐metal‐free conditions. The strategy uses cheap and commercially available PhI(OAc)2 as a promoter, TMSCF3 as a trifluoromethylation reagent in the presence of catalytic amount of benzoquinone to give the products in good yields. [ABSTRACT FROM AUTHOR]