A new synthetic approach to dihydrofuran derivatives via the annulation reaction of β-naphthols and 4-hydroxycoumarins with vinylsulfonium salts has been developed. A variety of dihydrofuran derivatives were prepared in moderate to good yields under mild conditions. The products could be readily transformed to the corresponding furans via the dehydrogenation with DDQ.

A base-mediated [3 + 3] benzannulation strategy for the conversion of 1,3-bis(sulfonyl)propenes and β,γ-unsaturated α-ketoesters to diaryl sulfones has been developed. This method provides facile, metal-free and efficient access to highly substituted diaryl sulfones in good to excellent yields. In addition, the sulfonyl group could be easily removed or converted to other functional groups via an organostannane intermediate.

Direct addition of tetrahydroisoquinoline derived amides to arylalkenes has been achieved in the presence of KOt-Bu/DMF. Both intermolecular and intramolecular reactions could occur in good yields. α-Amido alkyl radicals are proposed to be generated under the reaction conditions. The reaction is efficient for the synthesis of seven-membered nitrogen heterocycles. A homoprotoberberine was prepared conveniently via this method.

Hydrothermal reactions of metal nitrates and ligand bis(5-(pyridine-2-yl)-1,2,4-triazol-3-yl)methane (H L ) gave three cluster compounds, {Cr }, {Zn } and {Fe }. Notably, methylene group of H L was in situ oxidized either to hydroxymethylated (L -O) in the metallo-ring {Zn } or to a rigid carbonylated (L =O) in the screw-type {Fe }. In light of comparative experimental results, NO was deduced to be of a catalytic role in the ligand oxidation. Metal ion could be regarded as an "induced" tool for clusters generation in self-assembly process.

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