A copper-catalyzed oxidative dearomatization/spirocyclization of indole-2-carboxamides using tert-butyl hydroperoxide (TBHP) as the oxidant has been developed that provides rapid and efficient access to C2-spiro-pseudoindoxyls. Two sp2 C–H bonds are functionalized during reaction process, likely proceeds via formation a highly reactive 3H-indol-3-one intermediate followed by aromatic electrophilic substitution with N-aryl ring amide moiety.

An efficient cascade copper-catalyzed intermolecular Ullmann-type C–N coupling/enamine condensation reaction is described, in which ortho-acylanilines and alkenyl iodides converted to multisubstituted quinolines good excellent yields.

A highly efficient ZnCl2-catalyzed cascade reaction of enaminones with 2-furylcarbinols under mild conditions has been developed. This methodology offers a chemo- and diastereo-selective access to functionalized cyclopenta[b]pyrrole derivatives in good excellent yields.

A novel ring expansion reaction of indene-1,3-dione with alkynyl ketones under transition-metal-free conditions has been developed. This process offers an efficient and direct way to synthesize benzoannulated seven-membered rings or fused-ring compounds through C–C σ-bond activation. Notable features the procedure include easily accessible starting materials, good functional group tolerance, high atom economy.

Synthetic methods involving chemoselective tandem reactions for the synthesis of α-naphthylamines and indeno[1,2-c]pyrrolones starting from (o-aklynyl)phenyl enaminones are described. When were carried out in N,N-dimethylformamide (DMF) using a AgNO3 catalyst, obtained up to 89% isolated yields within 2 h. Whereas produced high presence benzoyl peroxide (BPO) CuCl catalysis.

Base-promoted C–C σ-bond insertion with methylene compounds bearing only one EWG (C–C insertion/cyclization).

Abstract Base‐promoted insertion reactions of alkynes into the C–C σ‐bonds α‐cyano ketones were established to construct highly functionalized conjugated olefins or chromone derivatives via transition metal‐free tandem reactions. These are initialized through nucleophilic attack alkynones followed by intramolecular addition/ring‐opening furnish cyano‐containing alkenes. In cases bearing an ortho ‐halide‐substituted aryl ring, a further C–O bond coupling reaction occurs afford in good high...

Transition-metal-free insertion of ynones into the C–N σ-bonds imides for chemo-selective synthesis chromones or enamides.

An efficient cascade β-metalation/addition/cyclization reaction promoted by LDA is described in which 3-amino furans were constructed from enaminones and aldehydes. A broad range of substituents on the starting compounds was tolerated, polysubstituted gained with moderate to excellent yields within 2 h.

An atom-economical procedure for the synthesis of pyranoindolones fused with 7- or 8-membered rings has been developed. This process is realized through sequential Cs2CO3-promoted C–C σ-bond cleavage cyclic ketoesters and a ZnI2-mediated selective C–H/O–H coupling reaction. Two σ-bonds are cleaved one sp2 C–H bonds functionalized during reaction process. Easily accessible starting materials broad substrate scope make this protocol attractive in synthetic organic chemistry.

Novel methods involving the chemoselective N-H or C-2 arylation for synthesis of indolo[1,2- a]quinoxalin-6-ones and 2,3'-spirobi[indolin]-2'-ones starting from indole-2-carboxamides were developed. When reactions carried out using ZnI2 as catalyst Ag2CO3 oxidant, synthesized in up to 86% yields via intramolecular N-H/C-H coupling, whereas dearomative cyclization realized presence TfOH, resulting indole through C-H functionalization a Fridel-Crafts alkylation reaction give moderate excellent yields.

A novel Pd/Cu catalytic system to construct indolo[3,2-c]quinolinones has been developed starting from indole-2-carboxamides. Substrates were transformed into through dual C(sp2)–H functionalization of the indole moiety and arene, in which a carbonyl 1,2-migration was involved. The corresponding products obtained moderate excellent yields with wide substrate scope.

An efficient and atom-economical methodology for the synthesis of multi-substituted carbazoles starting from α-aryl ketones ynones under mild reaction conditions has been developed. This process goes through Cs2CO3 promoted C-C σ-bond activation followed by highly selective C-H bond activations fragmentations in a one-pot operation.

An efficient and atom-economical silver-mediated [2 + 2 1] cyclization protocol for the synthesis of 3,4-fused-ring-substituted 2,5-unsubstituted selenophenes or thiophenes has been developed. Two C–Se/C–S bonds one C–C bond were rapidly constructed in step. Readily accessible substrates, commercially available elemental selenium/sulfur, good functional group tolerance make this procedure attractive π-conjugated material molecules.

A highly efficient protocol for the synthesis of polysubstituted cyano carbazoles has been developed. This process is realized through tandem reactions Cs2CO3 promoted C-C σ-bond activation α-cyano ketones followed by Fe-catalyzed selective C-H and/or bond activations. Two sp2 bonds are functionalized, and two σ-bonds cleaved involving a 1,2-acyl migration during reaction process.

An efficient and green route of C-C bond formation was disclosed to construct 2,3-diaryl-1,4-diketones from α-methylene ketones by the catalysis tetrabutylammonium iodide (TBAI) with tert-butyl hydroperoxide (TBHP) as an oxidant in water. This reaction affords desired products good excellent yields readily available materials, a broad substrate scope, functional group tolerance, mild conditions. Furthermore, tetrasubstituted furan pyrrole were smoothly constructed one pot 96 90% yields, respectively.

An unprecedented protocol has been developed for the preparation of highly functionalized chromeno[4,3-b]pyrrol-4(1H)-ones, which are not only valuable architectures many biologically active molecules but also key building blocks rich photophysical properties. The transformation proceeded through chemoselective intermolecular α-carbon nucleophilic attacking/ring-opening/Michael addition/deprotonation aromatization processes from 4-aminocoumarins and 2-furylcarbinols.

We report a four-component ring-opening reaction of pyrroles via C-N bond cleavage. In this process, elemental sulfur is used as the source thiazole and thioamide reductant olefin. A series benzothiazoles functionalized with thiopropionamides at C2 position were synthesized using method. plausible mechanism proposed based on concise control experiments.

A highly atom-economical protocol for the synthesis of tetrasubstituted furans has been developed. This process is realized through tandem reactions Cs2CO3 promoted C-C σ-bond activation α-aryl ketones followed by Zn-catalyzed intramolecular cyclization. represents first example preparation rearrangement molecular skeletons and subsequent transformations. Mild reaction conditions readily accessible starting materials make attractive in organic synthesis.

Abstract A highly efficient palladium‐catalyzed cascade reaction of propargyl carboxylates bearing a furanyl group with organoborons was developed. This methodology offers rapid access to polycyclic Diels–Alder cycloadducts in good high yields. The thus‐formed oxygen‐bridged products were further converted into anthracene derivatives chemoselective manner under mild conditions.

A novel and efficient synthesis of aza-eight-membered ring-fused indolines has been developed. This process is realized by zinc-catalyzed C2 alkylation indoles subsequent base-promoted ring expansion the newly formed six-membered with alkynes. Easily accessible starting materials, good functional group tolerance, high atom economy make this procedure attractive.

A dppb and TfOH promoted cascade reaction of o -nitrophenylpropiolamides to access C2-spiro-pseudoindoxyls under mild conditions is developed.

An efficient approach for the synthesis of 1,2-diaryl diketones was developed from readily available α-methylene ketones by catalysis I2. In same oxidation system, a novel one-pot procedure established construction antiviral and anticancer quinoxalines. The reactions proceeded well with wide variety substrates good functional group tolerance, affording desired compounds in moderate to excellent yields. Quinoxalines 4ca 4ad inhibited viral entry SARS-CoV-2 spike pseudoviruses into...

Abstract A novel Pd‐catalyzed method for the synthesis of indolo[1, 2‐ f ]phenanthridines from 2‐bromo‐2′‐iodo‐1,1′‐biphenyl and indole derivatives has been reported. The reaction involves direct N−H C2‐H arylation indole. This double provides a useful route to synthesize ]phenanthridine simple readily accessible starting materials.