A novel synthesis of unsymmetrical aryl sulfides, which requires no transition metal catalyst and no oxidant, was developed. This base-promoted cross-coupling reaction proceeded using arylhydrazines and 1 equiv amount of disulfides under inert gas conditions to afford the unsymmetrical aryl sulfides in good yields.

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Observations show that nitroanilines exhibit an unusually high S(N)Ar reactivity with OH(-) in aqueous media in reactions that produce nitrophenols. S(N)Ar reaction of 4-nitroaniline (2a) in aqueous NaOH for 16 h yields 4-nitrophenol (4a) quantitatively, whereas a similar reaction of 4-nitrochlorobenzene (1a) gave 4a in 2% yield together with recovered 1a in 97%, suggesting that the leaving ability of the NH(2) group far surpasses that of Cl under these conditions. An essential feature of S(N)Ar reactions of nitroanilines is probably that the NH(2) leaving group participates in a hydrogen-bonding interaction with H(2)O. Density functional theory (DFT) calculations for a set of 4-nitroaniline, OH(-), and H(2)O suggest a possible formation of a Meisenheimer complex stabilized by hydrogen-bonding interactions and a six-membered ring structure. The results obtained here contrast with conventional S(N)Ar reactivity profiles in which nitroanilines are nearly unreactive with nucleophiles in organic solvents.

An atom‐economical method for the synthesis of unsymmetrical diaryl selenides from arylhydrazines and stoichiometric amounts of diselenides was developed under mild conditions. The new and facile selenide synthesis involved the use of an inexpensive base in air to form unsymmetrical diaryl selenides in good yields. This C–Se radical arylation of diaryl diselenides was performed by forming aryl radicals from arylhydrazines under oxidative conditions. The formation of a phenyl radical was supported by trapping with 2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO) in air. Therefore, this synthesis might involve a homolytic aromatic substitution (HAS) mechanism. The synthesis is both low costing and environmentally friendly and, therefore, may be useful for the practical synthesis of unsymmetrical diaryl selenides.

Pairs of the skeletal isomers of eremophilane-type lactones were synthesized from furanofukinol via photosensitized oxygenation, followed by lactone cleavage and reformation. Their stereochemistry has been clarified so as to be consistent with a classification method outlined in our earlier papers.