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We have developed a new radical-mediated alkoxypolyhaloalkylation of styrenes with polychloroalkanes and alcohols for the facile synthesis of complex polyhaloalkanes. 4-Methoxybenzenediazonium tetrafluoroborate is a good radical initiator for this transformation. This protocol is well applied to the late-stage functionalization of complex molecules, including vitamin E, estrone and cholesterol derivatives.

A new, general Pd/Cu-cocatalysed dicarbonylative benzannulation of 3-acetoxy-1,4-enynes with CO and silylboranes is described. The method utilizes CO as both a one-carbon (C1) unit and an external addition functional reagent to achieve an unprecedented dicarbonylative benzannulation process, and represents a facile, efficient route to 3-hydroxyarylacylsilanes. Mechanistically, the silyl-Cu intermediate formed from CuF2 and silylboranes, and silyl-Pd intermediate generated by transmetallation are two key factors for successfully targeting the reaction and selectivity.

A three-component alkene alkylazidation using sodium azide as the azido resource and heteroarenium salts as functionalized alkyl reagents for producing highly valuable 2-azido-1-(1,4-dihydropyridin-4-yl)-ethanes is described. This reaction allows the incorporation of both an azido group and a 1,4-dihydropyridin-4-yl group across C[double bond, length as m-dash]C bonds to construct two new bonds in a single reaction step, and represents a practical and mechanistically distinct alternative that harnesses an electrophilic heteroarenium ion to accomplish the alkene difunctionalization reaction.

We here describe an alkynylative [5+1] benzannulation of 3-acetoxy-1,4-enynes with terminal alkynes, which enables both the construction of a benzene ring skeleton and intermolecular incorporation of an alkynyl group in a single reaction using Pd and Cu cooperative catalysts. The method represents efficient access to internal aryl alkynes through divergent functionalization of two terminal alkyne components: one alkyne serves as the one-carbon unit to realize the [5+1] benzannulation and the other alkyne as a nucleophile terminates the reaction.

A new silver-mediated 1,2-alkylesterification of alkenes with nitriles and acids promoted by a catalytic amount of nickel catalyst for producing acyloxylated nitriles has been developed via a C(sp3)–H functionalization process. By employing the NiI2 and Ag2CO3 catalytic systems, the method features broad substrate scope with respect to carboxylic acids, including linear alkyl acids, cyclic acids, aryl acids and amino acids.

A new, practical directed anodic C-H sulfonylation of N,N-disubstituted anilines with sodium sulfinates for producing o- or p-amino arylsulfones and diarylsulfones is described. Employing the anodic strategy, the reaction proceeds efficiently under mild (room temperature) and transition-metal- and chemical oxidant-free conditions, and enables the formation of C-S bonds via directed activation of ortho- or para-C-H bond to the amino group with broad substrate scope and excellent site selectivity.

A highly para-selective amination of anilines with phenothiazines for producing various functionalized 10-aryl-10H-phenothiazines is reported. The oxidative amination reaction proceeds electrochemically at room temperature, thereby avoiding the use of metals and oxidizing reagents with excellent functional group tolerance and broad substrate scope.

A new, catalyst-free tandem annulation route to 2,2-disulfonyl-2H-azirines via multiple-functionalizations of terminal alkynes with sodium sulfinates and tert-butyl nitrite is described. The use of sodium sulfinates and tert-butyl nitrite enables the formation of sulfonyl and NO radicals to selectively initiate and terminate the tandem annulation protocol, constituting a straightforward, conceptually different method to existing 2H-azirine synthesis techniques that currently require multiple steps by prior activation of the common starting materials.

The In(OTf)3-promoted three-component photoredox alkylarylation of styrenes with alkyl NHP esters and arenes to access alkylated arene derivatives through C-C bond cleavage and C-H functionalization is reported. By utilizing visible-light photoredox catalysis, alkyl N-hydroxyphthalimide esters serving as alkyl carbon-centered radicals and a wide range of arenes (e.g., indoles, pyrrole, and electron-rich arenes) as nucleophiles were used to enable the introduction of various alkyl groups and aryl groups across the C[double bond, length as m-dash]C bonds with excellent selectivity and functional group tolerance.

A new Lewis acid catalysed formal hetero-[5+2] cycloaddition of 2,3-dihydro-1H-pyrroles to terminal alkynes is described. By employing a FeCl3 and BF3·OEt2 co-catalytic strategy, the ring-opening of 1-tosyl-2,3-dihydro-1H-pyrroles by selective cleavage of the C(sp2)-N bond and subsequent annulation have been achieved to access 1-tosyl-2,3-dihydro-1H-azepines with excellent regioselectivity, offering a new avenue for cycloaddition through the ring-opening of non-strained-ring-based units.

A new, general silver-catalyzed oxidative 1,2-alkyletherification of unactivated olefinic ketones with primary, secondary and tertiary α-bromoalkyl carbonyls promoted by tert-butyl hydroperoxide (TBHP) and Et3N has been developed. Through the cooperative action of Ag2O, TBHP and Et3N, the reaction enables the construction of highly valuable quaternary-carbon-possessing 2,3-dihydrofuran frameworks using a concomitant intramolecular annulation strategy.

A new ruthenium(ii)-catalyzed electrooxidative [4+2] annulation of primary benzylic alcohols with internal alkynes is described, which enables benzylic alcohols as weakly directing group precursors to access isocoumarins via multiple C-H functionalization. The reaction works well with a broad substrate scope, tolerates a wide range of functional groups, and incorporates practically the isocoumarin unit into diverse bioactive molecules. Mechanistic studies indicate that activation of aryl C(sp2)-H bonds is achieved through the generation of the active benzoyloxy-Ru(ii) intermediates via oxidation of benzylic alcohols using an electrooxidative Ru(ii) catalyst.

A new copper-catalyzed three-component oxidative 1,2-trifluoromethylarylation of styrenes with NaSO2CF3 and indoles involving aryl C–H bond functionalization is described. This reaction is initiated by single electron transfer upon utilizing TBPB as an oxidant, thus enabling introduction of a CF3 group and an aryl group into the CC bond of alkenes in a single step. This method represents a highly atom and step-economical access to various CF3-substituted 1,1-diarylalkane derivatives in moderate to good yields with good functional group compatibility.

A Mn-promoted intermolecular oxidative radical heteroannulation of N-(2-cyanoaryl)-acrylamides and tertiary silanes has been described, which provides an efficient route to produce silicon/nitrogen heterocycles, sila-analogues of the known carbon-based structural motifs prevalent in bioactive natural products, pharmaceuticals and materials. The reaction enables Si-incorporation by controlling accurately several chemical bond cleavage and formation processes. Moreover, this reaction represents a new one-step construction of 1,3-azasiline-fused quinolinones that was achieved via silyl C(sp3)–H functionalization using an oxidative radical strategy.

For straightforward access to various substituted 1,1-diarylalkanes a photoredox-catalyzed and copper-promoted 1,2-alkylarylation reaction of styrenes has been developed, which uses α-carbonyl alkyl bromides and N,N-disubstituted anilines as functionalization reagents. In this radical difunctionalization reaction, α-carbonyl alkyl bromides, including primary-, secondary- and tertiary-α-bromoalkyl ketone esters, malonic esters and cycloalkane were transformed to the corresponding 1,1-diarylalkanes in moderate to good yields at room temperature. Notably, this transformation provided a new route for the C-H alkylation of N,N-disubstituted anilines with high para-selectivity beyond the typical Friedel-Crafts alkylation.

A new copper-catalyzed oxidative three-component intermolecular 1,2-alkylarylation of styrenes with ethers and indoles is disclosed. This method utilizes TBPB as an oxidant to efficiently construct C(sp3)–C(sp3) and C(sp3)–C(sp2) bonds in one step through probable radical and electrophilic alkylation processes, respectively, and a variety of functional groups are well tolerated.

A novel copper-promoted [2+2+2] annulation of 1,n-enynes with azobis(alkyl nitrile)s and H2O for the synthesis of diverse 7,8-dihydrophenanthridine-6,9(5H,6aH)-diones and fluorene is described. The reaction proceeds via the decomposition of azobis(alkyl nitrile)s into the cyanoalkyl radicals as the two-carbon units and offers a new efficient tool for the one-step formation of four new chemical bonds.

A new divergent intermolecular cascade annulation reaction of N-(arylsulfonyl)acrylamides with dual alkyl C(sp3)-H bonds for producing two types of five-membered rings, indanes and pyrrolidin-2-ones, is described. By using cycloalkanes and common alkanes as a one-carbon unit, an intermolecular [4+1] cascade carboannulation of N-(arylsulfonyl)acrylamides was achieved via a sequence of three C-H bond functionalization/aryl migration/desulfonylation that enables the formation of three C-C bonds and one N-H bond. When the one-carbon unit was changed to cycloalkyl ethers, the alternative intermolecular [4+1] cascade heteroannulation reaction occurred and allowed the construction of two C-C bonds and one C-N bond through dual C-H bond functionalization, aryl migration and desulfonylation cascades.

A new palladium-catalyzed dearomatizative [2 + 2 + 1] carboannulation of 1,7-enynes with aryl diazonium salts and H2O is presented. The reaction enables the construction of spirocyclohexadienone-fused cyclopenta[c]quinolin-4(5H)-ones through a sequence of Heck-type addition, 6-exo-dig cyclization, ipso-cyclization, dearomatization and hydrolysis.

A new copper-facilitated oxidative cyclization of 2-allenyl-1,1'-biphenyls with α-carbonyl alkyl bromides for producing functionalized phenanthrenes is presented, which represents the first allene 2,3-dicarbofunctionalization triggered by oxidative radical-medicated C3-addition of the terminal allene moiety and C-Br/C-H functionalization.

A Cu-catalyzed oxidative ipso-annulation of activated alkynes with unactivated alkanes for the synthesis of 3-alkyl spiro[4,5]trienones is described. This method allows the formation of two carbon-carbon bonds and one carbon-oxygen bond in a single reaction through a sequence of C-H oxidative coupling, ipso-carbocyclization and dearomatization.

The Cu-catalyzed oxidative [2+2+1] annulation of 1,n-enynes (n = 6, 7) with α-carbonyl alkyl bromides through C-Br/C-H functionalization has been developed. Using Ag2CO3/tert-butyl hydroperoxide (TBHP) as co-oxidants, α-carbonyl alkyl bromides provide two bonds, the α-C(sp(3))-Br bonds and the α-C(sp(3))-H bonds, to cyclize with the 1,n-enynes and Cu(MeCN)4PF6, thus forming three new C-C bonds and two rings in a single reaction.

A new palladium-catalyzed oxidative carbamoylation reaction of isoquinoline N-oxides with formylamides for the synthesis of isoquinoline-1-carboxamides is established. The method represents the first example of the carbamoylation of isoquinoline N-oxides with formylamides to furnish arylamides using the dual C-H oxidation strategy.

A new Rh(iii)-catalyzed oxidative bicyclization through C-H functionalization is presented. This reaction allows the selective assembly of diverse benzo[g]indoles from 4-arylbut-3-yn-1-amines and internal alkynes via a sequence of aromatic C(sp(2))-H functionalization, cyclodimerization and nucleophilic cyclization.

We here describe a new palladium-catalyzed oxidative 6-exo-trig cyclization of 1,6-enynes at room temperature using tBuONO as an oxidant for the synthesis of 3-bicyclo[4.1.0]heptan-5-ones. This cascade strategy involves the hydration, cyclization and cyclopropanation sequence, and represents a new transition-metal-catalyzed oxidative cyclization of 1,6-enynes in a 6-exo-trig fashion.

A new metal-free tert-butyl hydroperoxide (TBHP)-mediated carbonyl C(sp(2))-H oxidative alkynylation of aldehydes with ethynyl benziodoxolones (EBX) for the synthesis of ynones is described. This method is based on a carbonyl C(sp(2))-H oxidative radical coupling process according to mechanistic studies, and provides a general route to the assembly of diverse ynones with a broad substrate scope and excellent functional-group compatibility.