A palladium‐catalyzed C(sp2)−H difluoromethylation of aldehyde‐derived hydrazones using bromodifluoromethylated compounds to afford the corresponding functionalized difluoromethylketone hydrazones has been established. It is proposed that a radical/SET mechanism proceeding via a difluoroalkyl radical may be involved in the catalytic cycle. Applications of the methodology to the synthesis of α,α‐difluoro‐β‐ketoesters
The 3-chloroperoxybenzoic acid oxidation of dimethylhydrazones of aromatic aldehydes gives the corresponding nitriles in good yields. Two further examples of the same oxidative transformation of cinnamaldehyde and of hexanal are also given. Except for hexanal hydrazone, all other aldehyde hydrazones can also be efficiently converted into nitriles by treatment with methanolic 30 % hydrogen peroxide in the presence of catalytic amounts of selenium dioxide or, preferentially, 2-nitrobenzeneseleninic acid.