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Novel and efficient Mn(OAc)3⋅2H2O promoted radical addition-[4 + 1] cyclization relay of 3-indolymethanols and phosphites was disclosed, which afforded 1,2-oxaphospholoindole derivatives in moderate to good yields. Based on the experimental and computational studies, a mechanism involving radical addition and intramolecular cyclization cascade was proposed.

In many reactions involving selenosulfonate or thiosulfonate, the sulfone group often leaves in form of benzenesulfinic acid or sodium benzenesulfinate. A one-pot two-step reaction of selenosulfonate with isocyanides and allyl alcohol under aqueous conditions to afford selenocarbamates and allyl sulfone compounds is reported. The sulfinic acid as the first-step side product is converted to the allyl sulfone compound by water promoted reaction with allyl alcohol. Water acts as both an oxygen source of selenocarbamates and as a promoter to drive the second step reaction. The reactions have the advantages of mild conditions, green, environment-friendly, and high atomic economy.

A Mn(III) mediated radical reaction of new designed multi-functionalized 2-isocyano-6-alkenyl(alkynyl)benzonitriles with arylboronic acids has been developed. This reaction provides a method for the synthesis of pyrroloisoquinoline derivatives through the formation of two C C bonds and one C N bond via radical cascade cyclization in one step.

An efficient synthesis of 3-(diarylallylidene)oxindoles from 3-(1H-indol-3-yl)-1,1-diarylpropan-1-ol under metal-free conditions is described. NBS serves as a critical medium leading to a facile oxygen-migration in the transformation. The protocol has advantages of high efficiency, simple opreation, mild reaction conditions, good atom-economy, wide substrate scope and good yields of products. A detailed mechanism is proposed after careful investigation.

A TFA promoted multi-component reaction of aryldiazonium with sodium metabisulphite and thiols to construct thiosulfonates under transition-metal free conditions is reported. The thiosulfonates were isolated in good yields with broad tolerance of functional group. Readily available inorganic Na2S2O5 was applied as the sulfur dioxide surrogate. This strategy features easily available substrates, mild reaction conditions and free transition-metal catalyst.

A manganese(III)-promoted oxidative radical cascade reaction of easily accessible arylboronic acids with isocyanides to construct diimide derivatives was studied. This protocol provides a new way to synthesis of acetyl diimide derivatives. New C C, C N and C O bonds were formed in one step.

An efficient silver-catalyzed domino cycloisomerization reaction for regioselective assembly of 1 H -isochromene derivatives from o -alkynylaryl aldehydes with enaminones as the external nuclephiles is developed. This protocol affords isochromene derivatives in moderate to good yields under simple and mild reaction conditions.

Two novel oxazole derivatives 4-(6-(4,5-diphenyloxazol-2-yl)pyridin-3-yl)-N,N-diphenylaniline (TPA-PPO) and 2-(5-(4-(9H-carbazol-9-yl)phenyl)pyridin-2-yl)-4,5-diphenyloxazole (CzPh-PPO) have been designed and synthesized. The photophysical, electrochemical and thermal characters of the compounds were systematically investigated, which consistent well with the theoretical DFT calculations. TPA-PPO and CzPh-PPO exhibit high photoluminescent quantum yield of 0.63 and 0.59, respectively. The device using TPA-PPO as the dopant showed deep blue emission with a high EQE of 1.77%. A white OLED was obtained using the single emitter of CzPh-PPO with an EQE of 1.24%.

An organocatalytic asymmetric functionalization of C(3) S bond of indolone by naphthol is described. It provided a new and simple method for the construction of 3,3-disubstituted indolones containing a fresh-formed chiral quaternary carbon center with high yield and good enantioselectivity.

Readily available selenium powder was chosen as an ideal selenium source to construct a series of bis(arylethynyl) selenium compounds in moderate to excellent yields through the activation of terminal alkyne C–H bond mediated by AgF. The reaction has the advantages of easy operation, good substrate scope and high atom economy. In addition, tellurium powder was also successfully applied to this system for the construction of bis(arylethynyl) tellurides under identical conditions.

A series of air-stable aminocarbene-like palladium(II) complexes were easily prepared by the reaction of bis-aromaticisocyanide-dichloropalladium(II) with N-arylbenzamidines. 0.1 mol % of the optimal palladium complex 3a showed excellent catalytic activity for Suzuki–Miyaura cross-coupling reaction at room temperature and the desired products were isolated in up to 98% yields. Moreover, a large-scale reaction showed that 0.01 mol % 3a was enough to catalyze the coupling reaction efficiently at room temperature to give the desired product in 93% yield.

An efficient and practical protocol for copper-catalyzed aerobic oxidative dicarbonylation of indoles using α-carbonyl aldehydes to construct C-3 indole-substituted 1,2-diketones is developed. Various C-3 indole-substituted 1,2-diketones were observed in good to excellent yields under mild reaction conditions. This transformation used air as an ideal oxidant and produced water as the only by-product.

A palladium-catalyzed synthesis of aryl nitriles by the cyanation of aryl iodides with tert -butyl isocyanide as cyano source has been developed. This novel and efficient method avoids the use of toxic cyanides. The reaction is easy-to-handle and shows good functional group compatibility.

A convenient method has been established for the chemoselective synthesis of polyarylated oxazoles from aromatic aldehydes and 2-cyano heteroarenes. The protocol presents a novel one-pot methodology for the synthesis of oxazole derivatives without any metal catalysts or extra oxidants. Photophysical test showed that the polyarylated oxazoles may serve as potential fluorescent materials with blue light-emitting properties.

Two host materials, SFCA and SFCC, consist of a diphenylamine or carbazole unit linking to spiro-fused phenyl carbazole (SFC) backbone, were designed and synthesized. By choosing the meta linkage way between diphenylamine/carbazole units and SFC ring, higher triplet energies could be easily achieved for the two new materials, which mean that they could be used as effective host material for popular blue phosphorescent material Iridium(III) bis[(4,6-difluorophenyl)pyridinato-N,C 2′ ] picolinate (FIrpic, E T = 2.65). Besides that, the steric SFC structure could guarantee their good thermal stabilities. Their thermal, photophysical and electroluminescent properties were systematically investigated. The blue phosphorescent OLEDs with the two materials as hosts and FIrpic as a dopant exhibited excellent performance with maximum current efficiencies of 33.9 and 40.8 cd/A, respectively.

A new practical synthesis of phthalimides through 1,3-dipolar cycloaddition of CO2 with isocyanides and in situ generated aryne is reported here. A series of phthalimide derivatives are observed in moderate to good yields under mild conditions.

Reaction of anhydrous CoCl2 with NaOAr (OAr = 2,6-di-tert-butylphenoxo or 2,6-di-tert-butyl-4-methylphenoxo) in THF at room temperature afforded [Na(THF)6][Co(OArH)3] (1) and [Na(THF)5.33][Co(OArMe)3] (2) with Co–O(Ar) σ-coordination. The same reactions, proceeded first in THF and subsequently in hot toluene, led to the formation of a radical aryloxo sodium complex (3), as well as Co(π-OArMe)2 (4). Four complexes were characterized by X-ray crystallography.

A tandem reaction for the synthesis of chroman framework via a one-pot reaction of phenol, paraformaldehyde, and 5-benzylimidazolidin-4-one mediated by p-nitrobenzoic acid is described. The chroman derivatives containing spirocyclic N,O-acetal skeleton can be obtained in moderate to good yields (up to 89%) with good to excellent diastereoselectivities (up to >20:1 dr).

A NiCl 2 -catalyzed isocyanide insertion reaction of anilines bearing another nucleophile functional group utilizing TEMPO as oxidant in isopropyl ethanoate (IPA) or THF has been reported. This simple and general method could afford 2-aminobenzimidazole, 2-aminobenzothiazole, 2-aminobenzoxazole, as well as 2-aminobenzo[ d ][1,3]oxazine in moderate to excellent yields (up to 95% yield).

A silver-catalyzed 2-isocyanobiaryls insertion/cyclization with phosphine oxides was described for the construction of the 6-phosphorylated phenanthridines through radical addition of in situ formed P-centered radical to 2-isocyanobiphenyls and homolytic aromatic substitution process. The reactions could proceed smoothly to give the desired 6-phosphorylated phenanthridines promoted by AgOAc (20 mol %) with PhI(OAc)2 (3.0 equiv).

A novel multifunctional spiro-annulated fluorene/triarylamine based compound (STNPB) has been designed, synthesized and characterized. It exhibits a high glass transition temperature of 140 °C, due to the rigid spiro-configuration molecular structure. According to its suitable energy level and triplet energy (2.34 eV), improved performances, such as lower driving voltage, enhanced device power efficiency, and longer stability, are shown in organic light-emitting diodes with STNPB as the hole-transport material, compared with the ones with the widely used arylamine derivative N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-benzidine (NPB). Through further studies, it has been demonstrated that the enhanced stability is attributed to suppressed crystallization process as a result of employing STNPB instead of NPB as the hole-transport material.

An efficient Pd-catalyzed intramolecular indole-C2-arylation protocol for the synthesis of pharmaceutically active bis-indole alkaloid analogues from simple and readily available and 3,3′-Bis(1H-indol-3-yl)methanes derivatives has been developed. The corresponding products could be obtained in moderate to excellent yields, which permits selective modification on either one of the two indole moieties independently.

A simple and convenient synthetic approach to access of 3H-pyrrolo[2,3-c]quinolin-4(5H)-one derivatives by the reaction of (Z)-3-(2-oxo-2-ethylidene)indolin-2-one derivatives 1 with functionalized TosMICs under basic conditions has been reported. The desired products were obtained in good to excellent yields (82–94%). The easy accessibility of the starting materials, simple and mild reaction conditions, short reaction time, and good to excellent chemical yields make this methodology highly efficient.

An In(OTf)3-catalyzed N-benzylation of amines utilizing benzyl alcohols through direct C–O bond activation has been reported. The reaction was performed in water without any base, additive, ligand or inert gas protection to afford the chem-selective mono- or bis-alkylated aromatic amines in good to excellent yields.

A diastereoselective synthesis of 2-methyl-4-amino-1,2,3,4-tetrahydro-quinoline derivatives was achieved through the reaction of aromatic amines and tert -enamides in water under reflux conditions. The desired products could be obtained in moderate to excellent yields utilizing water as solvent without any catalyst or additive.

An efficient TFA-catalyzed cleavage of C–N bonds in alkylation of indoles by tertiary enamides was described. A variety of bisindolylalkane derivatives, especially 3,3-bisindolylpropanoates, were expeditiously synthesized in good yields.

A series of HSO 4 − functionalized ILs was synthesized and used as efficient, green, and metal-free catalysts for benzylation. Notably, the catalytic system has wide substrate scopes and the ionic liquid catalysts were applied to investigate three different types of nucleophiles to give the desired benzylation products with moderate to excellent yields.

An efficient method for the cross-coupling reactions of 1,3-dicarbonyl compounds with 2-oxo-1-pyrrolidine compounds 1 was developed. Cu(OTf) 2 catalyzed C–C bond forming reactions using substrates 1 with 1,3-dicarbonyl compounds in chloroform, providing the corresponding compounds of 2-oxo-1-pyrrolidine bearing 1,3-dicarbonyl moiety in moderate to good yields.

Four novel fluorescence dyes of the pyrazoline were synthesized and fully characterized by means of 1 H, 13 C NMR, and HRMS. The optical, electrochemical properties were also investigated. Solvent effect on the fluorescence characteristics of the four compounds indicates that the emission wavelength was red-shifted with the increase of solvent polarity. As we expected, the results indicated that these compounds exhibited high quantum yields. Quantum chemical calculations were used to obtain optimized ground-state geometry, spatial distributions of the HOMO, LUMO levels of the compounds.

Novel optical materials of trichromophore carbazole-pyrazoline have been synthesized and fully characterized by means of 1 H, 13 C NMR, and HRMS. The optical, electrochemical properties were also investigated. As expected, these compounds exhibited efficient emission from blue to green with high quantum yields. The solvent effect on the fluorescence characteristics of the four compounds indicates that the emission wavelength was red-shifted with the increase of solvent polarity. Quantum chemical calculations were used to obtain optimized ground-state geometry by hybrid density functional theory (B3LYP) with 6-31G* basis set, spatial distributions of the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) levels of the compounds.

A novel inorganic–organic photoluminescent (PL) and nonlinear optical (NLO) poly(3-dodecylthiophene)–CdS (P3DDT–CdS) with different molar ratios of CdS to P3DDT were synthesized via a oxidation coupling polymerization reaction and chemically hybridized approach, respectively. The P3DDT matrix possesses a highest-occupied molecular orbital value of about −5.87 eV determined from cyclic voltammetry. The third-order nonlinear optical susceptibility of P3DDT–CdS (−4.41 × 10 −12 esu) is higher than that of P3DDT and CdS, respectively. The coherent oscillation of the conduction band electrons in the nanocomposites is responsible for excellent NLO properties of P3DDT–CdS. The CdS particles as electron transport layer and photosensitizers had a nanoscale size in P3DDT adopting transmission electron microscopy. PL results show that, the electron-hole recombination occurred in the P3DDT is dominant, due to the valence band offset of P3DDT–CdS is higher than conduction band offset. The figures of merit of P3DDT and P3DDT–CdS are of −4.25 and −0.99, respectively. So, the P3DDT–CdS shows a potential application in the all-optical switching materials.

An efficient method for the construction of furo[2,3-b]indole derivatives 5 via an isocyanide-based multicomponent reaction (I-MCR) and a copper-catalyzed intramolecular Ullmann reaction sequence was described. This two-step sequence can be performed in a one-pot manner to produce the desired product 5 in moderate to good yield (up to 90%).

Accompanying with the construction of 1,4-dihydropyridine scaffold, indol-3-yl-5-oxo-1,4,5,6,7,8-hexahydroquinoline, and indol-3-yl-1,4-dihydropyridine derivatives were facilely synthesized through three-component reactions of aromatic aldehydes, 3-cyanoacetyl indoles with 3-amino-2-enones in the presence of ammonium acetate. The 1,4-dihydropyridine core structure can be efficiently aromatized in the presence of stoichiometric 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). This chemistry provides an efficient and promising synthetic strategy to diversity-oriented construction of unaromatized and aromatized desired products. The advantages of the present protocol are atom-economy, simple work-up and easy purification of products by non-chromatographic methods.

The aza-Michael addition of aromatic amines to α,β-unsaturated ketones was carried out effectively at room temperature in good to excellent yields without any catalyst or solvent. It was significant that part of adducts could be collected in almost quantitative yield without column chromatography. This procedure offered a green, efficient, and practical approach for the synthesis of β-amino ketones.

Reactions of isocyanides with 2-mercaptobenzothiazole and 2-mercaptobenzoxazole afforded a series of compounds containing formamidine framework in moderate to high yields. These organic transformations were performed under mild and catalyst-free conditions. In addition to promoting the reactions, the use of ultrasound irradiation also allowed the process to be carried out under air atmosphere. A possible reaction mechanism was proposed based on the experimental results.

A series of novel diamines linked by varying conjugated bridges were characterized using FTIR, NMR and UV–visible spectroscopy, mass spectrometry and elemental analysis. The photoluminescence and thermal properties of the compounds were related to structure and quantum chemical calculations were employed to study the optimized ground state geometry of the compounds. The diarylamines exhibited blue to green fluorescence emission and displayed high thermal stability and high glass transition temperature. As such, the compounds might be very useful as hole-transporting materials in organic light-emitting diodes.

Novel bipolar benzothiazole-based derivatives with various π -electron donors were synthesized and characterized using 1 H and 13 C NMR and mass spectrometry; their thermal, optical and electrochemical properties were also investigated. Optoelectronic properties are reported and discussed in terms of the distribution of the highest occupied molecular orbital and the lowest unoccupied molecular orbital and the conjugative pathway between the electron-donating moieties and electron-accepting moieties. The compounds exhibited high fluorescence quantum yield, desirable HOMO levels and high thermal stability. Quantum chemical calculations were used to study optimized ground-state geometry as well as spatial distributions of HOMO and LUMO levels of the compounds.

Nucleophilic substitution of ferrocenyl alcohols with N-, S-, O-centered nucleophiles promoted by a catalytic amount of cerium ammonium nitrate (CAN) was studied. By this protocol, a series of second arylamine, thioether, and ether were facilely synthesized in moderate to good yields under mild conditions.

A series of π-conjugated compounds were successfully synthesized by varying ratios of triphenylamine as donor (D) and benzothiazole as acceptor (A). The structure–property relationship about photoluminescence based on these synthesized compounds was systematically discussed in detail. Quantum chemical calculations were used to obtain optimized ground-state geometry by hybrid density functional theory (B3LYP) with 6-31G* basis set, spatial distributions of the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) levels of the compounds. As expected, these compounds exhibit high extinction coefficients, high quantum yields, and excellent thermal stability properties. The optical properties clearly indicate that the fluorescent emission properties of these compounds rely largely on the molecular structure.

Novel pyrazoline optical materials were synthesized and characterized using 1 H, 13 C NMR and HRMS; the thermal, optical and electrochemical properties of the compounds were also investigated. Solvent effects on the fluorescence of the six compounds indicated that the emission wavelength was red-shifted with increase in solvent polarity. Quantum chemical calculations were used to obtain optimized ground-state geometry as well as spatial distributions of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) levels of the compounds.

A series of dipolar quinoxaline derivatives with quinoxaline as core which carry pendant carbazole or triphenylamine moieties were synthesized and fully characterized. As expected, the compounds display bipolar character and can be explored as potential emissive and electron-transport materials as organic light-emitting diodes. Fluorescence spectra showed that the compounds exhibit excellent blue-green fluorescence.

The substitution reaction of ferrocenyl alcohol with various nucleophiles catalyzed by cerium ammonium nitrate (CAN) was investigated. This CAN-mediated direct carbon–carbon bond formation provides the corresponding products in moderate to high yields with relatively lower catalyst loading (5 mol %) at room temperature. It demonstrated a convenient synthetic protocol for the ferrocene functionalities.

Highly enantioselective asymmetric addition of terminal alkynes to various aromatic and heteroaromatic aldehydes catalyzed by the readily available, low-cost, and reusable resin-supported oxazolidine 4 together with Ti(OiPr)4 provides the chiral propargylic alcohols with good to excellent yields (up to 98%) and enantioselectivities (up to 95%). The immobilized catalyst can be recovered and used for five cycles.

A mild, efficient and environmentally friendly method has been developed for the synthesis of α-aminonitriles via a three-component condensation of aldehyde, amine and TMSCN in the presence of a catalytic amount of indium(III) iodide in water. The reactions proceeded smoothly at room temperature in water to generate the corresponding products in moderate to excellent yields.

Readily available copper powder with K2CO3 as the base was extremely effective catalyst for Suzuki–Miyaura coupling reaction performed in PEG-400, which afforded almost quantitative coupling products of aryl iodides. Using iodine as additive, coupling products of aryl bromides or chlorides could be obtained with moderate to good yields.

CuBr/rac-BINOL-catalyzed Sonogashira coupling reaction of aryl halides with terminal alkynes was conducted smoothly to afford the corresponding products with moderate to good yields. We found that the inexpensive catalytic system was also suitable for the coupling reaction of arylboronic acids with terminal alkynes.

A series of polysubstituted (3′-indolyl)pyrazolo[3,4-b]pyridine and (3′-indolyl)benzo[h]quinoline derivatives were synthesized via one-pot multicomponent reactions of aldehydes, 3-cyanoacetyl indoles with 5-aminopyrazol or naphthylamine under microwave irradiation. Particularly valuable features of this method include high yields of products, broad substrate scope, short reaction time and straightforward procedure.

A novel approach to one-pot synthesis of dihydrofuro[3′,4′:5,6]pyrido[2,3-c]pyrazole and indeno[2′,1′:5,6]pyrido[2,3-c]pyrazole derivatives have been investigated using organocatalysts that are recyclable. This new protocol has the advantages of environmental friendliness, higher yield, low cost, as well as convenient operation. The catalytic efficiency of various small organocatalysts such as l -proline, trans-4-hydroxy- l -proline, l -thiaproline, cinchonidine, (+)-cinchonine, and dl -2-phenylglycine has also been studied.

A series of 4-aryl-3,5-dicyano-2,6-di(3′-indolyl)pyridine derivatives were synthesized via a one-pot multicomponent reaction of aromatic aldehydes, 3-cyanoacetyl indoles, and ammonium acetate under microwave irradiation. Particularly valuable features of this method include high yields of products, broad substrate scope, short reaction time, and straightforward procedure.