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We report a general, practical and scalable hydroacylation reaction of ethylene with aromatic carboxylic acids with the synergistic combination of nickel and photoredox catalysis. Under ambient temperature and pressure, feedstock chemicals such as ethylene can be converted into high-value-added aromatic ketones in moderate to good yields (up to 92%) with reaction time of 2 - 6 hours.

An efficient photoredox radical borylation of electron-deficient Morita-Baylis-Hillman type alkenes is achieved to afford multi-functionalized allylic boranes. The reaction demonstrates a wide substrate scope and showcases excellent functional group tolerance. It has advantages over the traditional ionic hydroboration methods in the construction of allylic boranes in terms of simple operation, mild conditions, and step-economy.

A relay photoredox catalysis strategy concomitant with [1,5] hydrogen atom transfer has been applied in the construction of a biologically important indolo[2,1-a]isoquinoline framework via a cascade reaction. This reaction enables double C(sp 3 )-H bond functionalization and formation of two carbon-carbon double bonds from readily available starting materials in an efficient and step-economical manner.

A photosensitizer-free, highly efficient sunlight-promoted tandem [3+2]/[4+2] annulation of unsaturated α-bromocarbonyls with o-alkynylanilines was developed, and allowed for convenient synthesis of fused benzobicyclic skeletons. The reaction was clean and practical in mild conditions and showed excellent functional group compatibility.

The direct reduction of carboxylic acids to aldehydes with hydrosilane was achieved through visible light photoredox catalysis. The combination of both single electron transfer and hydrogen atom transfer steps offers a novel and convenient approach to selective reduction of carboxylic acids to aldehydes. The method also features mild conditions, high yields, broad substrate scope, and good functional group tolerance, such as alkyne, ester, ketone, amide and amine groups.

Chiral supramolecular assemblies (BNS-BPP) can be self-assembled by electrostatic and π-π stacking interactions between the chiral binaphthyl sulphonate (BNS) anion and the achiral bipyrene-based pyridinium (BPP) cation chromophore. BNS-BPP can exhibit strong CD and circularly polarized luminescence (CPL) signals, and the dissymmetry factor g lum values can be up to 0.079.

A general and efficient visible-light photoredox-catalyzed cascade annulation of 2-ethynylaldehyde hydrazones with α-bromo-carbonyls for the synthesis of various cyclohexylidene-hydrazine-fused polycyclic compounds is described. This protocol is characterized by a broad substrate scope, mild conditions and amenability to gram-scale synthesis.

A novel approach to obtain functionalized tetrazoles by a [3+2] cycloaddition of azide with aldehyde hydrazone is reported. This reaction features a broad substrate scope and mild reaction conditions through an aminyl radical-polar crossover strategy.

A new method for the synthesis of 3-arylindoles has been developed by visible light mediated dual gold/photoredox catalysis. This transformation has many features such as cascade catalysis, high efficiency, redox-neutral reaction conditions and good functional group tolerance. The reaction proceeds through the photoredox-promoted formation of an electrophilic arylgold(iii) intermediate that undergoes coupling with the arylamine nucleophile.

The functionalization of a cascade of C(sp(2))-H/C(sp(3))-H bonds in aldehyde hydrazones with simple 2,2-dibromo-1,3-dicarbonyls was achieved via visible-light photoredox catalysis. This method, which involves free radical addition, polar crossover and 6π electrocyclic reaction, provides an efficient approach for the synthesis of complex fused dihydropyrazoles and related derivatives with moderate to good yields and excellent regioselectivity under mild reaction conditions.

Visible light induced photoredox catalysis is an efficient method for radical activation. Herein, we report the photoredox catalysis involving an intramolecular radical-radical coupling reaction that proceeds through a biradical intermediate. This protocol represents a new synthetic route to construct multi-substituted N-heterocycles. Four, five and six-membered N-heterocyclic structures with a quaternary carbon center are accessible under mild conditions.

Oxazolo[3,2-a]indolone and spiro[furan-2,2'-indolin]one are synthesized by the visible-light-induced aerobic dearomative reaction of indoles. The common indole tethered alcohol at the N1 or C2 position reacts in a cascade fashion, providing facile access to diverse indolone scaffolds.

The TBPB promoted tandem oxidative C(sp(3))-H bond functionalization of simple alkanes/alkylation-initiated dearomatization of N-phenyl-cinnamamides is reported, providing a direct method for the synthesis of alkylated 1-azaspiro[4.5]decanes with excellent regioselectivity and diastereoselectivity. The formation of two C(sp(3))-C(sp(3)) bonds and construction of a spirodienone motif are involved in one step.

A novel visible light mediated radical cyclization of enol lactones with difluoroacyl arenes is presented. The reaction experienced a tandem radical cyclization and tolerated a wide range of substrates, resulting in fluorinated γ-butyrolactones in good chemical yield and with excellent diastereoselectivity.

Two AIE-active chiral BINOL-based O-BODIPY enantiomers (R/S-5) were synthesized and showed mirror-image red-color CPL induced via intramolecular energy transfer. The chiroptical properties of the molecules indicate that the chirality of electronic ground and excited states is stable and independent of aggregation.

A novel visible light promoted carbodifluoroalkylation of allylic alcohols is disclosed. A series of difluoro 1,5-dicarbonyl compounds were obtained through a tandem radical addition and 1,2-aryl migration process. Mechanistic analysis indicated that the 1,2-aryl rearrangement proceeded via a radical intermediate.

A metal-free radical oxidative decarboxylation/cyclization of acyl peroxides and 2-isocyanobiphenyls was achieved, leading to 6-aryl phenanthridines as well as 6-alkyl phenanthridines in moderate to good yields. The procedure featured simple conditions and was metal-free and base free. It represents a practical approach to access 6-aryl/alkyl phenanthridines.

A new synthetic strategy for C-C bond formation has been developed via a free radical cascade process under metal-free conditions. Activation of inert C(sp(3))-H/elimination of SO2/C-C bond formation were achieved in sequence in this system.

A novel halogenation/semipinacol rearrangement of α-diazo alcohol catalyzed by Lewis base has been developed through a carbene-free mechanism. This semipinacol transposition, initiated by an electrophilic halogenation (X = Cl(+), Br(+), and I(+)) of diazo carbon event, furnished a convenient synthetic route for the efficient synthesis of α-halo-quaternary ketones under mild conditions.

An effective approach to C1-difluoromethylated tetrahydroisoquinoline derivatives has been developed through C-H functionalization of tertiary amines by visible-light photoredox catalysis. This method uses stable, easily obtained α,α-difluorinated gem-diol as the CF2 source. The corresponding products were obtained in moderate to high yields at ambient temperature.

A visible-light-induced decarboxylative trifluoromethylation of α,β-unsaturated carboxylic acids, which uses the Togni reagent as the CF3 source is disclosed. The corresponding trifluoromethylated alkenes were obtained in moderate to high yields with excellent functional group tolerance at ambient temperature. Preliminary mechanistic analyses suggest a radical-type mechanism.

An Eu(III)-containing polymer can exhibit intense induced circularly polarized luminescence (CPL) in the presence of proline. In addition, the optical anisotropy factor (g(lum)) of the polymer for (5)D0 → (7)F1/(7)F2 transition was much higher than that of a single model molecule, which reveals the amplification effect of CPL arising from the conjugated polymer structure.

An elegant approach to quaternary oxindole formation has been developed through a room temperature decarboxylation/radical C-H functionalization by visible-light photoredox catalysis.

A new synthetic approach toward direct C-N bond formation through sp(3) C-H activation has been developed under metal-free conditions. Both primary and secondary benzylic C-H substrates could react smoothly with various amines to give only mono-amination products with good to excellent yields.

A novel chiral ionic polymer exhibits high fluorescence enantioselectivity towards α-amino acid anions, and its solution appears bright green upon addition of (L)-α-amino acid anions, which can be clearly observed by the naked eye for direct visual enantioselective recognition.

A palladium-catalyzed decarboxylative C2-acylation of indoles with α-oxocarboxylic acids was achieved. This protocol represents a novel and complementary approach to 2-aroylindoles.

A copper-catalyzed cross-dehydrogenative coupling reaction that involves C-H activation of formamides and N-H activation of N-alkoxy amides has been developed. This protocol affords a novel approach to the synthesis of multisubstituted ureas under mild conditions.

An organocatalytic cascade reaction that involves the formation of C-N, C-O and C=N bonds in one process via dual sp(3) C-H activation has been developed. This protocol affords a facile metal-free methodology for the synthesis of oxazole derivatives in air under mild conditions., (This journal is © The Royal Society of Chemistry 2012)

Mg(2+) can lead to the fluorescence enhancement of a dye molecule as high as 47.3-fold while L-proline acts as a promoter in this multicomponent sensory system. The fluorescence color could be easily detected by the naked eye under a UV-lamp., (This journal is © The Royal Society of Chemistry 2011)

The direct reductive amination of aromatic aldehydes has been achieved with excellent isolated yields (89-96%) using readily accessible Ph(3)PAuCl/AgOTf catalyst along with ethyl Hantzsch ester as hydrogen source under mild reaction conditions., (This journal is © The Royal Society of Chemistry 2011)

Oxidative α-cyanation of tertiary amines is catalyzed by gold complexes with trimethylsilyl cyanide to afford the corresponding α-aminonitriles in the presence of tert-butyl hydroperoxide in good to excellent yields under acid-free conditions at room temperature.

The desymmetrization ring opening of meso epoxides using trimethylsilyl cyanide catalyzed by organogallium and indium complexes with binaphthol monoether derivatives as chiral ligands gave beta-isocyanohydrins with moderate to excellent enantioselectivities of up to 95% ee.