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A new method for the AgSCF3-mediated radical cascade difunctionalizing trifluoromethythiolation of alkynes with dearomatization is developed. This protocol provides a novel route to SCF3-substituted spirocyclic compounds via the formation of one C-SCF3 bond, one C-C bond, and one C-O double bond in a single step.

A silver-promoted oxidative cascade cyclization with a phosphorylation/1,5-aryl migration/desulfonylation/dearomatization process is presented here, providing an efficient method to synthesize azaspiro[4.5]decenones with high regioselectivity. The cinnamamidyl radical, which has rarely been reported before, plays a key role in this reaction.

A novel iron-catalyzed aerobic oxidative reaction to synthesize disubstituted isoxazoles from homopropargylic alcohol, t-BuONO, and H2O is developed. The method provides mild conditions to afford a variety of useful substituted heterocycles in an efficient and regioselective manner. The mechanism has been studied and proposed, which indicates that the transformation can be realized through construction of a C═N bond and C═O bond, C-H oxidation, and then cyclization. Moreover, this method can be enlarged to gram scale.

A silver-promoted oxidative cyclization of 1,6-enynes with disubstituted phosphine oxides is developed for the synthesis of fluorene derivatives. The reaction proceeds with high regioselectivity by constructing one C-P bond and two C-C bonds in one step. Moreover, reduction of the pentavalent phosphine enlarges the application scope of the product.

A BF3·OEt2–AgSCF3 mediated direct trifluoromethylthiolation/cascade cyclization of propynols involving the SCF3 anion nucleophilic pathway is developed. This protocol also provides an opportunity to construct valuable trifluoromethylthio-substituted 2H-chromene and 1,2-dihydroquinoline systems with high efficiency under mild conditions. Additionally, the developed BF3·OEt2–AgSCF3 reaction system could be scaled up to gram quantities in a satisfactory yield without inert gas protection.