The rhodium(III)-catalyzed tunable oxidative cyclization of readily available N-tosylacrylamides and diazo compounds is presented, which offers a novel method for the selective construction of fully substituted α-pyrones and furans in a regiospecific manner by employing the acylsulfonamide group as a versatile in situ removable directing group.

A novel strategy to generate functionalized 1-azatriene intermediates for 6π electrocyclizations was developed by using readily accessible dienyne-imides and various terminal olefins under Pd catalysis. Taking advantage of the sequential cooperation between preloaded and incorporated functional handles at 1,3-dien-5-yne skeletons, this method not only enables the selective generation of putative 1-azatrienes but significantly accelerates their thermal 6π-electrocyclic ring-closure processes to a series of highly substituted furo[2,3-b]dihydropyridine derivatives in good yields.

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A formal palladium-catalyzed aerobic bimolecular carbocyclization reaction of (Z)-hexa-1,5-diyn-3-ene scaffolds has been successfully developed for the construction of 2,6-diacylnaphthalenes, wherein copper salts play a critical role in accomplishing the oxygenative homo- and hetero-dimerization processes of readily accessible enediyne-carboxylic acids and esters, respectively. The enediyne dimerization protocol provides a flexible and regiospecific approach to a variety of functionalized naphthalenes with up to six differentiated substituents in good yields by using a directing-group-assisted coupling and decoupling strategy. Mechanistic studies indicated that the two oxygen atoms being selectively incorporated into the crossover-annulation products of enediynecarboxylic acid and ester directly originate from atmospheric molecular oxygen and H2O, respectively.

A simple combination of CuI/LiOtBu/DMF enables the tandem Huisgen [3 + 2] cycloaddition/amidation reaction of terminal alkynes and sulfonyl azides to 5-sulfamide-1-(N-sulfonyl)-1,2,3-triazoles I, which can undergo an alkylation/desulfonation sequence to deliver highly substituted aminotriazoles II by one-pot or one-pot, two-step procedures.