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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 ligand-free nanoparticle ferroferric oxide catalytic system has been developed to promote the intramolecular C—N cross-coupling reaction. With this protocol, various 1,4-dihydroquinoline derivatives were synthesized from o-halobenzaldehydes and β-enaminones in moderate to good yields.

An efficient method for the synthesis of a series of ferrocenylcyclohexenones via tandem Michael–aldol reaction of ferrocenyl-substituted chalcones with dibenzyl ketone under solvent-free conditions is described. It was found that the factors including the electronic nature of chalcone, basicity of the base, reaction time, and temperature have effects on the formation of the ferrocenylcyclohexenones.

The Pd(OAc)2/DABCO catalytic system was first found to be highly efficient for C–N cross-coupling reactions. With the aid of this transformation, a variety of new 1,4-dihydroquinoline derivatives were synthesized from o-halobenzaldehydes and various β-enaminones in good to excellent yields. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Reaction of α-ferrocenyl alcohols with indoles in acetonitrilein the presence of Bi(NO 3 ) 3 ˙5H 2 Oafforded 3-alkylated indole derivatives in good yields and highselectivity. Bi(NO 3 ) 3 ˙5H 2 O provedto be an efficient catalyst in such a transformation.

A study of samarium powder-catalyzed cross-coupling reactions of aryl halides with terminal alkynes is described. The couplings performed in the polyethylene glycol PEG-600 provided the corresponding coupling products in good yields. The first example of palladium-free, copper-free and amine-free catalytic system for Sonogashira couplings is presented in the absence of ligand.

Ring-opening of two types of N-tosyl aziridines with hydroxyl compounds has been studied. The aziridines could react smoothly with alcohols in the presence of functional ionic liquid [hmim]HSO4 to afford the corresponding β-amino ethers in moderate to good yields with high regioselectivity. The recyclable property of [hmim]HSO4 was demonstrated in the process.

14-Aryl-1,6,7,14-tetrahydrodibenzo[a,i]acridine-1,6-diones have been synthesized in ionic liquid [bmim]BF4 (bmim=1-butyl-3-methylimidazolium) at room temperature. Particularly valuable features of this method include high yields of products, recyclable reaction media, broad substrate scope, short reaction time and operational simplicity.

A new series of indole-containing pyridine derivatives, 4-aryl-6-(1H-indol-3-yl)-2,2'-bipyridine-5-carbonitriles, were synthesized via one-pot multicomponent reactions of 3-(cyano-acetyl)indoles, aldehydes, heterocyclic ketones, and ammonium acetate. Particularly valuable features of this method include high yields of products, broad substrate scope, and straightforward procedures.

pH-responsive biodegradable micelles were prepared from block copolymers comprising of a novel acid-labile polycarbonate hydrophobe and poly(ethylene glycol) (PEG). Two new cyclic aliphatic carbonate monomers, mono-2,4,6-trimethoxybenzylidene-pentaerythritol carbonate (TMBPEC, 2a) and mono-4-methoxybenzylidene-pentaerythritol carbonate (MBPEC, 2b) were designed and successfully synthesized via a two-step procedure. The ring-opening polymerization of 2a or 2b in the presence of methoxy PEG in dichloromethane at 50 °C using zinc bis[bis(trimethylsilyl)amide] as a catalyst yielded the corresponding block copolymers PEG-PTMBPEC (3a) or PEG-PMBPEC (3b) with low polydispersities (PDI 1.03-1.04). The copolymerization of D,L-lactide (DLLA) and 2a under otherwise the same conditions could also proceed smoothly to afford PEG-P(TMBPEC-co-DLLA) (3c) block copolymer. These block copolymers readily formed micelles in water with sizes of about 120 nm as determined by dynamic light scattering (DLS). The hydrolysis of the acetals of the polycarbonate was investigated using UV/vis spectroscopy. The results showed that the acetals of micelles 3a, while stable at pH 7.4 are prone to rapid hydrolysis at mildly acidic pH of 4.0 and 5.0, with a half-life of 1 and 6.5 h, respectively. The acetal hydrolysis resulted in significant swelling of micelles, as a result of change of hydrophobic polycarbonate to hydrophilic polycarbonate. In comparison, the acetals of PMBPEC of micelles 3b displayed obviously slower hydrolysis at the same pH. Both paclitaxel and doxorubicin could be efficiently encapsulated into micelles 3a achieving high drug loading content (13.0 and 11.7 wt %, respectively). The in vitro release studies showed clearly a pH dependent release behavior, that is, significantly faster drug release at mildly acidic pH of 4.0 and 5.0 compared to physiological pH. These pH-responsive biodegradable micelles are promising as smart nanovehicles for targeted delivery of anticancer drugs.

An intriguing new Wacker-type oxidation of alkynes catalyzed by PdBr(2) and CuBr(2) is described, which opens an efficient access to 1,2-diketones using molecular oxygen. Under the optimized conditions, a variety of alkynes, including diarylalkynes, arylalkylalkynes, and dialkylalkynes, were compatible substrates in this transformation. The mechanism of this reaction was preliminarily investigated by control experiments.

A simple and efficient synthesis of spiro[indoline-3,4′-quinoline] derivatives by a one-pot reaction of isatin, malononitrile, and enaminone under microwave irradiation was investigated. This protocol has the advantages of short reaction time, high yields of products, broad substrate scope, and easy workup procedure.

Suzuki-type coupling reactions can be performed directly in air using a catalytic system composed of iodine, potassium carbonate, and polyethylene glycol 400 (I 2 /K 2 CO 3 /PEG-400). Iodine was found to be an effective additive for accelerating these couplings. The methodology is also suitable for the coupling of (E)-β-bromostyene with phenylboronic acid, with retention of the double bond geometry.

The alkali salt of L-proline was demonstrated to be an efficient and practical catalyst for the cyanosilylation of a wide variety of simple and functionalized carbonyl compounds under solvent-free conditions. The reactions proceeded smoothly at room temperature to afford the corresponding cyanohydrins in good to excellent yields.

An efficient catalyst-free synthesis of α,α-bis(4-hydroxycoumarin-3-yl)toluene was performed by the reaction of 4-hydroxycoumarin with aromatic aldehydes in aqueous media under microwave irradiation. The reaction was completed in short reaction time of 8–10 min with high yields of 76–94, was environmental benign, and had easy workup. Their structures were confirmed by IR spectra, 1H NMR, 13C NMR, and elemental analysis.

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.

A series of quinoxaline derivatives was synthesized by the reactionof 3-(ω-bromoacetyl)coumarins with substituted 1,2-diaminobenzenesin the absence of a catalyst under microwave conditions. Reasonableyields of the products, environmentally benign and convenient workupare the advantages of this method.

Ligand-free iron/copper cocatalyzed cross-coupling reactions of aryl halides with terminal alkynes were carried out to provide the corresponding coupling products in good yields (up to 99%). Noteworthy is that this low-cost, effective and environmentally friendly protocol was the first to be employed in alkynylation couplings.

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.

Copper-catalyzed cross-coupling reactions of aryl halides and heteroaryl halides with terminal alkynes were carried out in DMF at 110–130 °C to provide the corresponding coupling products in satisfactory-to-good yields by using inexpensive 8-hydoxyquinoline as the ligand. Noteworthy is that the bifunctional copper catalyst was successfully applied in this alkynylation reaction for the first time.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

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.

An efficient and straightforward copper-catalyzed method allowing vinylation of N-nucleophiles with various substituted ( £ )-vinyl bromides under palladium-free and ligand-free conditions has taken a high yield (up to 95%). Noteworthy is that the double-bond geometry of these vinyl halides was retained with our protocol.

A new chemosensor for Cu2+ was synthesized based on 1,2,3,4,5,6,7,8,9,10-decahydroacridine-1,8-dione dyes, which exhibited an obvious fluorescent selectivity to the sensing of Cu2+ ions over other cations, such as Na+, K+, Ca2+, Cd2+, Co2+, Hg2+, Mg2+, Mn2+, Ni2+, Zn2+, Ag+ and Pb2+. Moreover, it presented a fluorescent switch function when EDTA was added to the compound-Cu2+ complex in examined systems.

A series of pyrimido[4,5-b]quinoline and indeno[2′,1′:5,6]pyrido[2,3-d]pyrimidine derivatives were synthesized via the three-component reaction of an aldehyde, 6-aminopyrimidine-2,4-dione and 5,5-dimethyl-1,3-cyclohexanedione or 1,3-indanedione in ionic liquid 1-n-butyl-3-methylimidazolium bromide ([bmim]Br). This protocol has the advantages of easier work-up, milder reaction conditions, high yields and an environmentally benign procedure compared with other methods.

Catalyzed by molecular iodine at room temperature, under solvent-free conditions, a two component aza-Diels-Alder cyclization of N-vinyl-2-pyrrolidinone with N-arylimine gave tetrahydroquinoline derivatives in good yields and high stereo-selectivity. And three components aza-Diels-Alder reaction of N-vinyl-2-pyrrolidinone, anilines and indole-3-carbaldehydes under the same condition afford only cis-product in good 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.

3-Amino-benzo[d]imidazo[2,1-b]thiazoles were synthesized in moderate to good yields in the presence of NH 4 Cl via a one pot procedure. All the products were characterized by 1 H NMR, IR, HRMS.

A series of novel 1,8-naphthalimide derivatives have been synthesized via Suzuki cross-coupling and characterized by 1H NMR, IR and elemental analysis, with their luminescent properties, quantum yields and electronic properties also presented. These compounds exhibited orange fluorescence with the maximum wavelengths ranging from 584 to 610 nm and lower HOMO energy level.

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.

Ferric dodecyl sulfonate [Fe(DS)3] is easily prepared and can be used as a Lewis acid surfactant catalyst in water to conduct the highly efficient electrophilic substitution reaction of indoles with aliphatic or aromatic aldehydes at room temperature.

The conjugate addition reactions of amines with 1,4‐naphthoquinone were catalyzed efficiently by molecular iodine under ultrasonic irradiation to afford 2‐amino‐1,4‐naphthoquinones in moderate to excellent yields.

A novel method for the Michael reaction of indoles to α,β‐unsaturated ketones catalyzed by acidic ionic liquid is reported. We obtained the corresponding products in excellent yields in the presence of [hmim]HSO4. Development of this method has resulted in a new protocol for the synthesis of β‐indolylketones.

A highly efficient asymmetric conjugate addition of methylmagnesium bromide (MeMgBr) to α,β-unsaturated esters catalyzed by copper(I) iodide-tolyl-BNIP (CuI-Tol-BINAP) is described.

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.

Various tri(indolyl)methanes were synthesized by condensation of indole and its derivatives with indole-3-carboxaldehyde using acidic ionic liquids [hmim]HSO4/EtOH as an efficient and green catalyst system.

A novel highly selective fluorescent Zn2+ chemosensor bearing terpyridyl and naphthalimide was synthesized, which exhibited very obvious fluorescent response to Zn2+ and was remarkably selective to Zn2+ than other metal ions such as Zn2+, Pb2+, Cd2+, Cu2+, Hg2+, Ca2+, Mn2+, Mg2+, Fe3+, Co2+, Ni2+ and Ag+.

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.

A series of novel carbazole-naphthalimide compounds with moieties capable of carrier-balance and electroluminescence were synthesised and characterised, and theirs luminescent properties had been studied.

The reaction of various indoles (1a–1k, 3 equiv.) with triethyl orthoformate (1.2 equiv.) catalyzed by I2 (5 mol%) at room temperature in 2–15 min under a solvent-free condition afforded the respective symmetrical triindolylmethanes (3a–3k) in good to excellent yields without any side products.

An efficient copper-catalyzed amination of nitrogen-containing heterocycles with various aryl halides has been developed. Commercially available and inexpensive hippuric acid is a novel ligand to afford the coupling products in moderate to excellent yields.

A systemic and comprehensive study has been made on the formation of 3H-(pyrrol-1-yl)indolin-2-ones synthesized from various isatin derivatives and 4-hydroxyproline catalyzed by InCl3 under a refluxing condition in excellent yields (83%–99%) and purity.

A series of novel bischromophore compounds containing pyrazoline and naphthalimide were synthesized, and their structures were confirmed by means of IR, 1 H NMR, UV and elementary analysis. The fluorescent spectrum showed that these compounds had good green fluorescence. The fluorescence emission wavelengths varied from 520 to 540 nm.

A copper(I)‐catalyzed intramolecular amination reaction using CuI, KOH, and 1,4‐dioxane at 105°C for the preparation of 1‐aryl‐1H‐indazole derivatives was described. The method was applied to a wide scope of substrates and afforded indazole products in high yields.

In(DS)3 catalyzes formation of 9H‐xanthen‐9‐ol with indoles at room temperature in water to afford a class of 3‐(9H‐xanthen‐9‐yl)‐1H‐indole derivatives in high yields.

A Pd-catalyzed highly regioselective 6-exo-dig cyclization/alkenylation reaction of ortho-ethynylanilides has been developed. This tandem cross-coupling protocol represents a simple, efficient, step- and atom-economic approach for the construction of scarcely known polyene-substituted benzo[d][1,3]oxazines in moderate to excellent yields with a broad substrate scope.

A palladium-catalyzed efficient C–H acylation reaction of biaryl-2-amines and aromatic aldehydes is developed. This dehydrogenative cross-coupling protocol could furnish monoacylation and diacylation products in moderate to good yields with a broad substrate scope and good regioselectivity.

This novel strategy for preparation of the sterically hindered title compounds involves chemoselective isocyanide insertion followed by domino isomerization.