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A copper-catalyzed four-component trifluoromethylthio-arylsulfonylation between styrene derivatives, AgSCF

A dual nickel-/palladium-catalyzedgem-difluorovinylation of alkynyl bromoarenes is presented. This method proceeds smoothly to afford various dihydrobenzofuran compounds containing gem-difluorovinyl fragments with excellent stereoselectivities.

A new metal- and base-free method for synthesizing sulfonylated pyrrolin-2-ones from 1,5-dienes, aryldiazonium salts and SO2 is presented. This transformation features mild reaction conditions and broad substrate scope.

We presented an efficient method to access gem-difluoro-2-trifluromethyl styrene derivatives via palladium catalysis, which features mild reaction conditions and broad substrate scope.

A palladium-catalyzed domino Heck cyclization/carbonylative Hiyama-Denmark cross-coupling reaction between alkene-tethered aryl iodides and silylcarboxylic acids is presented. This reaction proceeds well without toxic carbon monoxide (CO) gas and has good functional group tolerance, providing an alternative access to carbonyl-containing oxindoles. In this transformation, silylcarboxylic acids play a dual role as a CO source and a nucleophile.

A copper-catalyzed four-component chloro-arylsulfonylation of styrene derivatives with aryldiazonium tetrafluoroborates, lithium chloride, and ex-situ generated sulfur dioxide (from SOgen) is presented. This sulfonylation features good functional group compatibility, mild reaction conditions, excellent regioselectivity, and good yields. The robustness and potential of this method have also been successfully demonstrated by a gram-scale reaction. Based on experimental study, a radical-involved mechanism is proposed for the transformation.

A nickel-catalyzed cross-electrophile coupling of allylic acetates and

A 1,3-sulfonyl migration of difluorovinyl sulfonates initiated by a catalytic amount of silver fluoride is presented. α,α-Difluoro-β-ketosulfones were successfully prepared in excellent yields. This method features high chemoselectivity, good functional group tolerance, high atom economy, and mild, environmentally benign reaction conditions. Furthermore, mechanistic experiments indicate that this migration proceeds in an intermolecular pathway and the corresponding sulfinates are possible intermediates.

A nickel-catalyzed cross-electrophile coupling reaction between (hetero)aryl bromides and 2,2-difluorovinyl tosylate is presented. This protocol provides facile incorporation of the gem-difluorovin...

A ligand-free iron-catalyzed method for the oxygenation of benzylic sp3 C–H bonds by molecular oxygen (1 atm) using a thiyl radical as a cocatalyst has been developed. This transformation provides a facile access to amides, esters and ketones from readily accessible corresponding amines, ethers and alkanes. It features high regioselectivity, mild oxidative conditions and excellent functional group compatibility, providing good opportunities to the site-selective functionalization of complex molecules. Preliminary mechanistic studies suggest that this reaction may not undergo a benzylic cation intermediate pathway and the carbonyl oxygen atom in the products may be derived from molecular oxygen.

A 1,3-sulfonyl migration of difluorovinyl sulfonates initiated by a catalytic amount of silver fluoride is presented. α,α-Difluoro-β-ketosulfones were successfully prepared in excellent yields. This method features high chemoselectivity, good functional group tolerance, high atom economy, and mild, environmentally benign reaction conditions. Furthermore, mechanistic experiments indicate that this migration proceeds in an intermolecular pathway and the corresponding sulfinates are possible intermediates.

Cross-coupling between substrates that can be easily derived from phenols is highly attractive due to the abundance and low cost of phenols. Here, we report a dual nickel/palladium-catalyzed reductive cross-coupling between aryl tosylates and aryl triflates; both substrates can be accessed in just one step from readily available phenols. The reaction has a broad functional group tolerance and substrate scope (>60 examples). Furthermore, it displays low sensitivity to steric effects demonstrated by the synthesis of a 2,2’disubstituted biaryl and a fully substituted aryl product. The widespread presence of phenols in natural products and pharmaceuticals allow for straightforward late-stage functionalization, illustrated with examples such as Ezetimibe and tyrosine. NMR spectroscopy and DFT calculations indicate that the nickel catalyst is responsible for activating the aryl triflate, while the palladium catalyst preferentially reacts with the aryl tosylate.

A ligand-free iron-catalyzed method for the oxygenation of benzylic sp3 C-H bonds by molecular oxygen (1 atm) using a thiyl radical as a cocatalyst has been developed. This transformation provides a facile access to amides, esters and ketones from readily accessible corresponding amines, ethers and alkanes. It features high regioselectivity, mild oxidative conditions and excellent functional group compatibility, providing good opportunities to the site-selective functionalization of complex molecules. Preliminary mechanistic studies suggest that this reaction may not undergo a benzylic cation intermediate pathway and the carbonyl oxygen atom in the products may be derived from molecular oxygen.