Search

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 photoredox-/copper-catalyzed decarboxylative difluoroacetylation reaction of α,β-unsaturated carboxylic acids has been developed. This reaction produces a variety of difluoroalkylated alkenes in moderate to excellent yields and exhibits satisfactory stereoselectivity and a broad substrate scope at ambient temperature. Furthermore, this decarboxylative difluoroacetylation protocol provides efficient and environment friendly access to the difluoroalkylated alkenes.

A remote OH group-directed metal-free transformation of alkynes to carbonyl compounds has been developed. Using only HOAc and EtOH solvent, this reaction elegantly converts alkynes into valuable ketones by remote hydroxyl group activation. Through comparison and isotope labeling experiments, it was confirmed that the process operates via a hydration reaction involving an acetic acid molecule, instead of a water molecule.

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 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 remote OH group-directed metal-free transformation of alkynes to carbonyl compounds has been developed. Using only HOAc and EtOH solvent, this reaction elegantly converts alkynes into valuable ketones by remote hydroxyl group activation. Through comparison and isotope labeling experiments, it was confirmed that the process operates via a hydration reaction involving an acetic acid molecule, instead of a water molecule.

A strategy for the synthesis of 6,9-dihydropyrido[1,2-a]indoles through a cascade iodocyclization of 4-(3-methyl-1H-indol-1-yl)-1,1-diphenylbut-2-yn-1-ol derivatives is presented. This reaction was conducted under very mild conditions and in a short time. The reactions are metal-free, are environmentally friendly and give up to 94% yield. Moreover, the obtained halides allow functional group diversification by palladium-catalyzed coupling reactions, which could act as potential intermediates for the synthesis of valuable compounds.

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.

An unprecedented Lewis acid catalyzed [4 + 3] cycloaddition reaction is described that provides a straightforward route to polycyclic products containing an imine-based indole azepine scaffold, starting from readily available internal tertiary alkynols and azides. This cycloaddition protocol provides efficient and atom-economical access to a new class of fascinating imine-containing products in satisfactory yields, which has shown good application in the construction of seven-membered N-heterocycles.

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.

A novel and convenient metal-free nitration and cyclization of 1,6-enynes has been developed. Two C-C bonds and one C-N bond were constructed in one process in this reaction. This transformation is proven to have relatively good functional-group applicability and can be scaled up to gram quantities in satisfactory yields. According to the following experimental facts and related literature reports, a radical pathway was involved in this transformation.

The scalable iron-catalyzed aerobic oxidative reaction is influenced by the steric hindrance of the substrates′ aryl substituents.

The reduction of the pentavalent phosphine in the products to a trivalent one is demonstrated for one product (XII).

A novel and convenient metal-free nitration and cyclization of 1,6-enynes has been developed. Two C-C bonds and one C-N bond were constructed in one process in this reaction. This transformation is proven to have relatively good functional-group applicability and can be scaled up to gram quantities in satisfactory yields. According to the following experimental facts and related literature reports, a radical pathway was involved in this transformation.