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Silver-catalyzed oxidative decarboxylative couplings of carboxylic acids and anhydrides to produce 1,2-diketones and substituted ethanes were developed. This reaction allows the generation of acyl or alkyl radicals by decarboxylation of the corresponding -keto acids, alkyl acids and anhydrides, which are sequentially coupled to efficiently construct a new C-C bond. This reaction represents a carboxylic acid decarboxylative alternative that employs a radical termination strategy.

A new metal-free oxidative cascade methylation/cyclization of benzene-linked 1,7-enynes is described for the construction of methylated polyheterocyclic scaffolds skeletons. In this transformations, three new C-C bonds and two new rings were formed. Notably, di-tert-butyl peroxide (DTBP) acts not only a radical initiator but also an efficient methyl source.

We here describe a new copper-catalyzed tandem annulation of alkenes with α-bromoalkyl esters and primary amines for producing polysubstituted pyrrolidin-2-ones. The reaction allows the formation of three new chemical bonds, one C-C bond and two C-N bonds, in a single reaction, and represents the first three-component difunctionalization of alkenes for the synthesis of pyrrolidin-2-ones involving [2+2+1] annulation.

A new, radical-mediated, divergent bicyclization of 1, n-enynes by alpha-C(sp(3))-H oxidative functionalization of alkyl nitriles is described using the Sc(OTf)(3) and Ag2O system. The reaction allows the selective functionalization of one or two C(sp(3))@H bonds a to the nitrile group by both oxidants and the substitution effect co-controlled the divergent bicy-clization reactions, and offers a step-and atom-economical access to diverse polycycles with broad substrate scope and high selectivity.

A new copper-mediated synthesis of alpha-sulfonylethanone oximes from styrenes, sodium arylsulfinates and tert-butyl nitrite ( t-BuONO; TBN) is presented. This intermolecular three-component method enables the one-step formation of C-N and C-S bonds under mild conditions, and represents a new, straightforward approach to alpha-sulfonylethanone oximes.

A new, metal-free, radical-mediated oxidative decarbonylative hydroalkylation of various alkynes with secondary and tertiary alkyl aldehydes using di-tert-butyl peroxide (DTBP) as oxidant is presented. This method enables the simultaneous formation of a CC bond and a CH bond through a sequence of decarbonylation, radical addition and protonation, and provides a straightforward route for transforming alkynes into alkenes with high compatibility with both alkynes and alkyl aldehydes.

A new visible light-initiated 1,5-hydride radical shift strategy has been developed to enable the one-step functionalization of both a C(sp3)Br bond and a C(sp3)H bond adjacent to the same carbon atom. This visible light photoredox catalysis offers a mild and straightforward access to diverse five-membered carbocyclic ring-fused polycyclic hydrocarbons with high turnover numbers (TONs; up to 4.93×103) and broad substrate scope.

A metal-free radical-mediated [4+2] annulation of internal arylalkynes with tert-butyl nitrite (t-BuONO) is presented for the synthesis of benzo[e][1,2]oxazin-4-ones through the addition of t-BuONO across the C C triple bond, hydration, isomerization and aromatic C(sp(2)) H oxidation cascades. The O-18-labeling experiment shows that two oxygen atoms in the product system are from water.

2,3-Epoxy ketones [(III) and (V)] are synthesized through an oxidative radical pathway with a broad substrate scope and excellent selectivity control.

A new silver-catalyzed oxyfluorination of unactivated alkenes using commercially available Selectfluor as the fluorine source is presented. This method provides a new access to 5-(fluoromethyl)4,5-dihydroisoxazoles, and represents a new example of alkene 1,2-difunctionalization by simultaneously forming two new carbon-heteroatom bonds.

An efficient copper-catalyzed α-aminoxylation of ketones with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) is presented.The copper on iron catalyst can be recovered and reused several times with high catalytic reactivity.

A wide range of quinolinones is prepared using carbocyclization of α-C(sp3)-H bonds of amides with alkynes followed by ketonization of the alkynes.

A novel palladium-catalyzed CH oxidation of isoquinoline N-oxides has been developed for regioselectively synthesizing substituted isoquinolines. The method represents the first example of using dialkyl sulfoxides as the alkyl sources for the construction of 1-alkylated isoquinolines. Moreover, the regioselective halogenation of isoquinoline N-oxides is also successful using dihalo sulfoxides as the halide sources.

A selective and general route to (E)-1,3-diaryl-prop-1-enes and (E)-3-arylallyl acetates has been developed by palladium-catalyzed Heck-type reactions of allylic esters with arylboronic acids or potassium aryltrifluoroborates. The present method selectively proceeds including β-OAc elimination or β-H elimination on the basis of the boronic acids. Whereas a variety of allylic esters were reacted with arylboronic acids, palladium(II) acetate [Pd(OAc)2], tetra(n-butyl)ammonium chloride [(n-Bu)4NCl] and postassium dihydrogen phosphate (KH2PO4) to afford the corresponding diarylation products in moderate to good yields, treatment of allylic esters with potassium aryltrifluoroborates furnished the corresponding monoarylation products.

A novel palladium-catalyzed intramolecular tandem annulation method is presented for the synthesis of 3-[5H-dibenzo[b,e]azepin-11(6H)-ylidene]indolin-2-ones. This method allows the conversion of various 3-[2-(2-iodobenzylamino)aryl]-N-arylpropiolamides to the corresponding 3-[5H-dibenzo[b,e]azepin-11(6H)-ylidene]indolin-2-ones through the diarylation of an alkyne.

A new, general method for the synthesis of phenanthridines has been developed by palladium-catalyzed oxidative remote CH olefination–carboamination–CC bond cleavage tandem reaction. It is noteworthy that alkenes are used as the one-carbon resources for this tandem reaction.

Palladium-catalyzed direct mono- and diarylations involving C(sp3)H cleavage at the γ-position of acrylamides are described. The monoarylation products can be obtained with ortho-substituted aryl halides. Single crystal X-ray diffraction has shown that the double bond has shifted towards the introduced aryl group to afford the γ-arylated β,γ-unsaturated amide products. A second arylation occurs when less sterically hindered aryl halides are employed. This chemistry offers a novel disconnection for the synthesis of γ-arylated compounds.

An efficient synthesis of N-methyl-3-chalcogeno-indoles has been developed via iodine-mediated electrophilic annulation reactions of 2-alkynylaniline derivatives with disulfides or diselenides. In the presence of iodine and iron, a variety of 2-alkynylanilines selectively underwent the electrophilic annulation with numerous disulfides or diselenides leading to the corresponding 3-sulfenylindoles and 3-selenenylindoles in moderate to excellent yields. It is noteworthy that iron can promote the reaction.

An efficient and resuble copper on iron catalyst has been prepared for the cleavage of the carbon-carbon o-bond in α-aminocarbonyl compounds leading to the corresponding formylamides and acids with a maximal TON of up to 51,000. It is noteworthy that the copper on iron catalyst can be easily separated from the reaction mixture, and retains its activity after several reuses.

The first example of the synthesis of 4,5-disubstiuted furan-2(5H)-ones by base-mediated tandem acyl shift/cyclization/decarbonylation reactions of aroylmethyl 2-alkynoates has been developed. This new and inexpensive tandem route allows both a C―O bond and a Csp 3 ―Csp 2 bond forming in one step involving an unprecedented acyl rearrangement process.

A simple, versatile new approach to four-membered ring to six-membered ring products has been developed by zinc-catalyzed intramolecular Conia-ene reactions of 1,3-dicarbonyl compounds with alkynes. This new route allows a wide range of dicarbonyl compounds, including the classically challenging 1,3-diesters and N,N'-disubstituted 1,3-keto amides, to be used for the Conia-ene reaction with inexpensive zinc chloride (ZnCl 2 ) under neat conditions.

3-Sulfenylindoles can be efficiently prepared in moderate to good yields from 2-(1-alkynyl)benzenamines and disulfides using the palladium/ air catalytic systems. The study also provides a useful route to the synthesis of fipronil analogues.

A highly practical method for the synthesis of 2-aminobenzothiazoles has been developed through an iron-catalyzed tandem reaction. The present tandem process allows the assembly of a wide range of 2-aminobenzothiazoles by the reactions of 2-halobenzenamines with isothiocyanates.