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• Ipso -nitration protocol of aliphatic and (hetero)aromatic carboxylic acids. • Free from a toxic metal catalyst and harmful volatile organic solvents. • 1-Hexyl-3,4,5-trimethyl-1H-imidazolium and nitronium cations are used. • Applicable to the gram-scale synthesis of nitro compounds. • Usage of ionic fluids reduces waste solvent production significantly. An eco-friendly and a simple ipso -nitration protocol for a series of aliphatic and (hetero)aromatic carboxylic acids using nitronium tetrafluoroborate, 1-hexyl-3,4,5-trimethyl-1H-imidazolium tetrafluoroborate and base is reported. While contrasted with recently known decarboxylative ipso -nitration strategies for the preparation of nitro compounds, this protocol does not require a toxic metal catalyst and harmful volatile organic solvents. Moreover, this method is perfect for a broad range of functional groups and affords exclusively the ipso -nitrated product in moderate to good yields. [ABSTRACT FROM AUTHOR]

• New potential chromene based non-linear optical (NLO) dyes were prepared. • The benzopyran fragments is a very promising acceptor for design of NLO chromophores. • High values of the first hyperpolarizability achieved for benzopyran chromophores. • Reversible solvatochromism was obtained for chromene-based chromophores. A series of new chromophores based on 4-(dicyanomethylene)-2-vinyl 4H-chromenes was synthesized and their physical properties (UV–Vis, NMR, mass spectrometry) were studied. The chromophores show moderate or good solubility in organic solvents. Solvatochromism was investigated for compounds in solvents of low (1.4-dioxane, chlorobenzene, methylene chloride) and high polarity (acetone, acetonitrile). The calculations of the first hyperpolarizability (β) was performed using M052X/6-31+G(d) approximation. Chromophore's molecules are characterized by high calculated values of the first hyperpolarizability (β) that is only 15% lower than that of FTC analogs. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Practical one-pot reaction for preparation of 5-substituted-1 H -tetrazoles. • Without using high boiling point or volatile organic solvents in the reaction. • Easy reaction set-up and multigram scale. Abstract A series of 5-substituted-1 H -tetrazoles have been efficiently synthesized in moderate to excellent yields (68–90%) under mild reaction conditions by combining aryl aldehydes, hydroxylamine hydrochloride with sodium azide in the presence of catalytic amount of Cu(OAc) 2 in deep eutectic solvent (DES). The new synthetic method has many advantages, such as high conversion, green reaction medium, easy work-up, low cost, and environment friendly. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Silica gel-mediated hydrohalogenation of alkenes was developed. • Widely available hydrohalogenic acids can be employed. • Reactions proceeded under organic solvent-free conditions. • Silica gel can be recycled without significant loss of activities. Abstract Silica gel-mediated hydrochlorination of unactivated alkenes using 35% hydrochloric acid under organic solvent-free conditions proceeded to give the corresponding chlorides in good yields. Hydrobromination or hydriodination using 47% hydrobromic acid or 55% hydriodic acid afforded the corresponding halides, respectively. Silica gel could be recycled five times without any significant loss of activities. [ABSTRACT FROM AUTHOR]

Efficient aliphatic radiofluorination in a mixed organic solvent system was investigated. This method obviates the time-consuming [ 18 F]fluoride drying step routinely required in the preparation of most fluorine-18 positron emission tomography (PET) radiotracers. The [ 18 F]fluoride ions eluted from a QMA (quaternary ammonium anion exchange) cartridge with phase transfer agents were directly mixed in various organic solvents for subsequent radiofluorination. Herein, we report the azeotropic drying-free radiofluorination of aliphatic substrates and demonstrate the viability of hydrated [ 18 F]fluoride ions in a mixed organic solvent system for obtaining useful radiochemical yields (RCYs). This practical and simple method has demonstrated general applicability to the production of established PET tracers as well as to the rapid assessment and chemical optimization of early-stage potential radiotracers. [ABSTRACT FROM AUTHOR]

In this research, green synthesis of imidazo[1,2- a ]pyridines in the presence of calix[ n ]arenes-SO 3 H as a Brønsted acid catalyst and surfactant is described. Using of calix[ n ]arenes in water provided a hydrophobic cavity that successfully carried out the synthesis reactions at short times with high yields. This catalyst system is recoverable with a simple extraction using an organic solvent and reusable for at least for 5 cycles without any losses of its activity. [ABSTRACT FROM AUTHOR]

The mechanochemical synthesis has provided a greener alternative to solution-based approaches by eliminating the use of organic solvents and reducing the energy consumption. The C–H functionalization is among the most concise and economical synthetic strategies. The combination of the benefits from these two methods provides new opportunities to further increase the efficiency and sustainability of organic synthesis. In this digest, we aim to provide a brief overview of the recent advances in mechanochemical C–H functionalization reactions. [ABSTRACT FROM AUTHOR]

The excellent catalytic potential of sulfated polyborate is utilized in the synthesis of (un)symmetrical ureas and benzimidazolones by heating amines or substituted OPDA and urea or N -phenylureas under a solvent-free condition at 120 °C is described. The key advantages of the present protocol are phosgene-free, and other hazardous reagents or organic solvent free, high reaction rates and yields, simple workup procedure, and recyclability of the catalyst. [ABSTRACT FROM AUTHOR]

1,3,5-Tris-( o- carboranyl-methyl)benzene ( closo - 1) and its nido -form ( nido - 1 ) were synthesized and fully characterized. The solid-state molecular structure of closo - 1 was determined by single-crystal X-ray diffraction analysis. Compound closo - 1 exhibited an intense single emission in various organic solvents that was red-shifted with increasing solvent polarity. The positive solvatochromic effect and theoretical calculation results at the first excited (S 1 ) optimized structure of closo - 1 strongly suggest that this emissive band can be assigned to an intramolecular charge transfer. Meanwhile, nido - 1 showed a pronounced red-shift of the emissive band compared to that of closo - 1 and aroused low-energy emission. The specific emissive features of nido - 1 were attributed to the elevation of its HOMO level, estimated by cyclic voltammetry. The photophysical changes by conversion from closo - 1 to nido - 1 allowed the emissive color-tunable sensing of fluoride. Thus, the tris- o -carboranyl compound showed great potential as a chemodosimeter for fluoride anion sensing, detectable by the naked-eye. [ABSTRACT FROM AUTHOR]

A group of new low molecular weight organogelators based on threefold symmetric tricarbamate were synthesized and characterized. The tricarbamates with long alkyl chains were able to gelate a wide range of polar and nonpolar organic solvents such as acetonitrile and cyclohexane, generally at concentrations lower than 20 g/L. The best organogel formation was obtained using a threefold symmetric tricarbamate in n -dodecane, in which a sufficiently transparent gel was formed at the critical gelation concentration 1 g/L. Intermolecular hydrogen bonding by the tricarbamate in a nonpolar solvent benzene- d 6 was indicated by 1 H NMR spectra. Its maximum UV absorption was 11 nm higher in chloroform than in n -dodecane, and this red shift indicated increased conjugation between the benzene core and the carbamate substituents, which confirmed a change in its conformation from nonpolar to polar solvent. The self-assembling behavior of the tricarbamate in dilute solutions was investigated by TEM. Fiber-like networks were observed in a large range of solution concentrations. [ABSTRACT FROM AUTHOR]

To develop reaction systems of chemical conversion of biomass, fructose was heated in an aqueous medium under pressurized CO 2 , which caused in situ generation of carbonic acid. It gave 5-hydroxymethyl-2-furfural (HMF) as a dehydration product in good yields. The maximum yield of HMF was 92% in the reaction at 90 °C under 7.0 MPa of CO 2 for 168 h. The reaction proceeded in the absence of any other reagents such as non-volatile acids, organic solvents, inorganic, and organic salts. It means green, environmental-friendly, and efficient process was achieved for production of HMF. [ABSTRACT FROM AUTHOR]

An unexpected and intriguing reaction to the direct construction of indolo[2,3- b ]quinoline ring system of neocryptolepine analogues was discovered through simple heating of 3-acetyl-2-ethoxyindole with isatins in 10% aqueous ethanol media with the presence of KOH as the base. The process is very clean and avoids the use of toxic organic solvent, thereby enhancing the greenness of the transformation. Moreover, the newly-synthesized compounds bearing a pendant carboxyl group at the C-11 position of indolo[2,3- b ]quinoline skeleton could be potentially applied as useful synthetic building blocks for more complex indolo[2,3- b ]quinoline alkaloid derivatives. [ABSTRACT FROM AUTHOR]

The combination of choline chloride and urea as a deep eutectic solvent has been applied to the synthesis of benzo-fused seven-membered heterocycles, including tricyclic 1,4-benzodiazepines and 1,4-benzoxazepines, via a one-pot, three-component reaction. The reaction conditions are relatively mild and do not require additional metals, acid catalysts, or organic solvents. The protocol has the advantages of excellent yields in short reaction times, an easy workup procedure, and being environmentally friendly. [ABSTRACT FROM AUTHOR]

We described the practical synthesis of β-acyl glucuronide from allyl 2,3,4-tri-( O -allyloxycarbonyl)- d -glucuronate ( 5 ) mediated by 1-chloro- N , N ,2-trimethyl-1-propenylamine (TMCE). A wide range of bulky carboxylic acids (aryl carboxylic acids or tertiary-carbon-linked carboxylic acids) were employed to give the corresponding β-acyl glucuronate in good yields. The side products of this reaction are only N , N -dimethylisobutyramide and HCl. As the resulting acyl glucuronates show sufficient solubility to organic solvent, it can be easily purified by conventional silica gel column chromatography and/or crystallization, even in multigram quantities. The allyloxycarbonyl group and allyl group are cleanly removed by Pd(0), and thus the protocol can provide multigram quantities of β-acyl glucuronides with high purity. [ABSTRACT FROM AUTHOR]

This Letter describes the use of alkene-terminated polyisobutylene (PIB) as a support for oxidizing agents. Two oxidizing agents, an ionically immobilized PIB-bound perruthenate oxidation catalyst and a PIB-bound 2-iodoxybenzoic acid (IBX) oxidizing reagent, were studied. A perruthenate catalyst ionically bound to PIB was prepared by binding the perruthenate anion to PIB that contained either a terminal tetraalkylammonium or an imidazolium salt. The PIB supported ammonium and imidazolium perruthenate were both selectively soluble in heptane and effective in the oxidation of alcohols. While these PIB-bound perruthenate catalysts could be readily separated from products, recycling was less successful. A PIB bound 2-iodoxybenzoic (IBX) oxidizing agent was coupled to a PIB support with an ester bond. It was highly soluble in nonpolar and moderately polar organic solvents. By taking advantage of PIB’s heptane solubility, the spent IBX reagent could be easily separated from products by a liquid/liquid heptane/acetonitrile biphasic separation. The recovered IBX reagent could then be regenerated and used in multiple cycles for oxidation of both primary and secondary alcohols. [ABSTRACT FROM AUTHOR]

Here we report that two boron dipyrromethene derivatives ( BNB-1 and BNB-2 ), bearing double boron atomic centers, have been synthesized and characterized. The additional boron atom was introduced into the skeleton of typical BODIPY dyes through the reaction of BF 3 ·Et 2 O and the two ligands, phenol and Schiff’s base. The maximum emission wavelength of both dyes moved to 584–603 nm with the larger Stokes’ shift (Δ λ ≈ 40 nm). Moreover, less solvent polarity dependence of the Stokes’ shift (40 ± 6 nm) was found in different organic solvents. Furthermore, fluorescent lifetime and CV methods were also performed to explore the photophysical and electrochemical behaviors of both dyes. [ABSTRACT FROM AUTHOR]

The fluorophore 2,6-bis(2-methoxyphenyl)dithiazolo[4,5- b :5′,4′- e ]pyridine) 3 , with a planar structure, was synthesized using a one-pot Willgerodt–Kindler reaction which is potentially applicable to various dithiazolopyridines. The basic photophysical characteristics were investigated in organic solvents of different polarity. Chemosensor 3 exhibits a ‘turn-off’ response toward Cu 2+ and Fe 3+ ions, as well as a new emission wavelength-ratiometric response to H + ions, illustrating a different recognition manner. From the binding constant calculations of 3 with Cu 2+ , increased sensitivity for the fluorescence method over that of the UV–vis method was found, while both methods showed similar sensitivity for binding of 3 with H + . On the other hand, the different behavior in the complexes of 3 ·H + and 3 ·Cu 2+ under cyclic voltammetric analysis was observed. These findings suggest that compound 3 may have potential as a sensor for water pollution by Cu 2+ and Fe 3+ ions as well as protons. [ABSTRACT FROM AUTHOR]

An efficient protocol for the synthesis of various substituted phenylpiperazines was developed using sulfolane as solvent. The protocol was clean, high yielding and products were obtained in high purities (⩾99%). It was also fast and convenient, as the final products were precipitated as hydrochloride salts and could be obtained by filtration. Sulfolane, an aprotic, dipolar, high boiling and recoverable solvent was used as a substitute for common organic solvents. [ABSTRACT FROM AUTHOR]

To develop the utilization of HI as an ‘old but new’ reagent, we found that the reaction of acetophenone analogues with HI gas proceeded to give an α-alkylated product, which is derived from the two ketone molecules. It was possible to conduct the reaction in solvent-free and various organic solvents under anhydrous conditions. From the investigation on the reaction mechanism, we proposed that HI acts as an acid and a reducing agent. [ABSTRACT FROM AUTHOR]

Bioimprinting is a technique in which an aqueous solution of a protein molecule along with the imprint molecule is dried to remove bulk water. Subtilisin was dissolved in an aqueous buffer with a substrate analog and precipitated with the substrate alcohol to obtain a dually bioimprinted enzyme precipitate. Precipitation was found to be a better bioimprinting technique than freeze drying used so far. The precipitation also enabled simultaneous bioimprinting with the alcohol substrate reinforcing the existing imprint with the substrate analog. The dually bioimprinted subtilisin was found out to be 65-fold more efficient than the freeze dried non-imprinted powder of subtilisin and could transesterify N -acetyl- l -phenylalanine with n -propanol up to 82% in 5 h. [ABSTRACT FROM AUTHOR]

A simple, highly efficient and environmentally benign method for the synthesis of quinoxalines has been developed using a green and recyclable catalyst Amberlite IR-120H resin under solvent-free conditions. This method avoids environmentally harmful conventional organic solvents. Interestingly, the catalyst can be recovered after completion of the reaction and can be reused as the catalytic property of the resin is not effected even up to four cycles. Therefore, this method provides a green and much improved protocol over the existing methods. [ABSTRACT FROM AUTHOR]

Subtilisin lyophilized from its solution in aqueous buffer in the presence of 6 M urea showed up to 50-fold increase (as compared to lyophilized subtilisin not subjected to urea treatment) in its initial rate of a transesterification reaction in anhydrous n -hexane. The lyophilization time controlling the extent of ‘drying’ was an important parameter. The urea treated subtilisin had five times shorter half life during heating at 100 °C in hexane. The change in conformation was also reflected in its 92-fold higher activity at 15 °C as compared to merely 28-fold higher activity at 45 °C. The comparative enantioselectivity of urea treated subtilisin during kinetic resolution of 1-phenylethanol was expectedly lower. Its enantioselectivity during kinetic resolution of a natural substrate N -acetyl-( R , S )-phenylalanine ethyl ester in hexane was higher. Urea treated subtilisin also showed higher catalytic promiscuity during an aldol condensation. CD studies in both far UV and near UV region were also carried out to compare the two structures. [ABSTRACT FROM AUTHOR]

[Display omitted] • An AIE-active pyran-based derivative with no flexible chains could gelate organic solvents. • Halogen-aided balanced intermolecular π-π interactions plays important role in the gelator's self-assembly. • The pyran derivative shows tri-colored high-contrast mechanochromism with excellent repeatability. An AIE-active pyran derivative bearing bromine, but no alkyl chains or amide units was found to be able to gelate organic solvent aided by the halogen-assisted balanced intermolecular π-π interactions. Moreover, the pyran derivative exhibits tri-colored high-contrast mechanochromism based on the transition between monomer and different π dimers. [ABSTRACT FROM AUTHOR]

[Display omitted] • The investigation of the applicability of CO 2 as a solvent is important. • The CO 2 -expanded liquids as solvents for a lipase-catalyzed reaction were examined. • CO 2 -expanded MeTHF accelerated the reaction rate by up to 40 times that without CO 2. • Chiral tetralols, important drug intermediates, were synthesized (ee up to > 99%). The investigation on the applicability of CO 2 as a solvent has been increasingly important due to the need to develop efficient reactions replacing ordinary organic solvents derived from fossil fuel with sustainable solvents such as pressurized CO 2. In our previous study of solvent engineering of a lipase-catalyzed reaction of bulky substrates, the conversions were higher for the reaction in CO 2 -expanded liquids, liquids expanded by dissolving pressurized CO 2 , than that in the liquids without CO 2. This study demonstrates the detailed examination of CO 2 -expanded liquids as solvents for lipase-catalyzed kinetic resolution of racemic 1-tetralol, 2-tetralol, and substituted 1-tetralol analogs since chiral substituted tetralol analogs are important pharmaceutical intermediates. CO 2 -expanded liquids accelerated the reaction rate by up to 40 times of the reactions without CO 2 while maintaining excellent enantioselectivities (E > 200). Preparative scale reactions of racemic 1-tetralol and 2-tetralol successfully gave the corresponding (R)-acetates and (S)-alcohols with high yields and excellent enantioselectivities (up to ee > 99%). [ABSTRACT FROM AUTHOR]

[Display omitted] • Low-cost Transition metal catalyst is used for the synthesis. • Use of environmentally benign water as a solvent. • No organic solvent is used. • Both pyrazoles and phthalazin-1(2H)-ones are synthesized from the same starting material. • Reactions proceed at room temperature. Herein an efficient and simple protocol was developed for the synthesis of pyrazoles and phthalazin-1(2H)-ones from a common precursor hydrazines catalyzed by nickel chloride. The reactions proceeded in water at room temperature. The advantages of the protocol are that both the medicinally important scaffolds could be synthesized with low-cost catalyst, green solvent, relatively lower reaction time and superior yield of the product making the protocol synthetically very useful. Electronically diversed pyrazoles and phthalazinones could be achieved in good to excellent yields in relatively shorter reaction time. [ABSTRACT FROM AUTHOR]

The reactions of 2-amino-5-cyclopropylpyridine with organic nitrites in the presence of copper(II) halides in various organic solvents were investigated. Optimal reaction conditions for the Sandmeyer reaction were developed and successfully applied to the synthesis of useful building blocks, bromo and chlorocyclopropylpyridines. Aminocyclopropylpyridines were synthesized in high yields from the corresponding aminobromopyridines under standard Suzuki coupling conditions. [ABSTRACT FROM AUTHOR]

A new and highly efficient enzymatic aminolysis approach for kinetic resolution of aromatic α-hydroxy acid in non-aqueous media has been developed. The corresponding α-hydroxyl acid ester was employed as the substrate, and commercially available Candida antarctica lipase B is used as the biocatalyst, anhydrous ammonia is the resolving agent. Reactions can be proceeded smoothly in organic solvent at ambient temperatures. High concentration of substrate is allowed due to the application of organic media and the products are obtained in yields of up to 49% with ee values of up to 99%, and with E value of >300, representing an appealing and promising protocol for large-scale preparations. [ABSTRACT FROM AUTHOR]

The reaction of 2,5-bis-(α-arylhydroxymethyl)thiophenes with 5-aryldipyrromethanes in the presence of acidic ionic liquid gives 21-thia-5,10,15,20-tetraarylporphyrins in 30% yield whereas the reaction of 2,5-bis-(α-arylhydroxymethyl)thiophenes with 5,10-diaryltripyrromethane or pyrrole gives 21,23-dithia-5,10,15,20-tetraarylporphyrins in 35% yield. Acidic ionic liquids are better catalyst and reaction media than acid catalysed reaction in organic solvents for the synthesis of core modified porphyrins. [ABSTRACT FROM AUTHOR]

Abstract: A convenient route for the synthesis of triazole fused benzoxazepines or benzodiazepines in aqueous micellar medium has been described. The two step one-pot synthesis involves Sonogashira reaction of prop-2-ynyl 2-azidobenzoates and aryl iodides followed by intramolecular azide–alkyne cyclization using Pd(CH3CN)2Cl2 as catalyst and ethanedial,1,2-bis(2-methyl-2-phenylhydrazone) as ligand, under atmospheric condition. The method excludes the use of copper salts as catalyst as well as hazardous organic solvents. [Copyright &y& Elsevier]

Abstract: AgBArF displays remarkable ‘on-water’ activity for catalytic hydration of terminal alkynes although it is ineffective in common organic solvents. Liquid alkynes do not require additive or co-solvent whereas a small amount of ethyl acetate triggers quantitative conversions for solid alkynes. [Copyright &y& Elsevier]

Abstract: 1-n-Butyl-3-methylimidazolium fluoride ([bmim][F]) proved very efficient fluorinated reagent for nucleophilic substitution over sulfonate esters and alkyl halides. Preparation of the ionic liquid as well as its use as the reagent has been performed to be the more eco-friendly as possible. No organic solvent is needed for the fluoride introduction, reaction times are reduced by using microwave as the heating source, and the ionic liquids carefully recycled. Furthermore, no special care has to be taken as the presence of water in [bmim][F] was not deleterious to the transformation yield. [Copyright &y& Elsevier]

Abstract: Cell-bound lipases of dry mycelium of Aspergillus oryzae were used in organic solvent for the resolution of racemic flurbiprofen by direct esterification with ethanol in a flow-chemistry reactor. Under flow conditions a significant reduction of the reaction time and an increase of the enantioselectivity were achieved compared to the batch mode. Moreover, the process was implemented by adding an in-line purification step integrated with the racemization of the unreacted flurbiprofen directly into a polymer-supported resin. [Copyright &y& Elsevier]

Abstract: A selective hydrogen peroxide oxidation of sulfides to sulfoxides using Ti-MWW and Ti-IEZ-MWW catalysts was developed. This reaction was carried out under organic solvent-free conditions, and the only side-product was water. Improvement of catalytic activity toward bulky sulfides will be achieved by optimization of the topology in the Ti zeolite. [Copyright &y& Elsevier]

Abstract: An effortless and efficient protocol was developed for the synthesis of N,N′-diarylsubstituted formamidines under environment-friendly conditions. Ultrasonic energy was employed to obtain the desired products in excellent yields with high purity under solvent-free and catalyst-free conditions. Products were purified by the crystallization technique to avoid excess utilization of organic solvents. [Copyright &y& Elsevier]

Abstract: Novel low-molecular-weight amorphous organic glasses based on triphenylamine core end-capped by either di(4-methoxyphenyl)amino or 3,6-dimethoxycarbazol-N-yl groups have been synthesized and characterized. The molecules exhibit high glass-transition temperatures (74–151°C), excellent thermal stability, and are soluble in common organic solvents. Moreover, most of them absorb mainly in UV domain. These star-shaped triphenylamine derivatives are promising hole transporting materials for solid-state dye-sensitized solar cell applications. [Copyright &y& Elsevier]

Abstract: 3-(Pyridylmethyl)-3-hydroxy-2-oxindole derivatives were synthesized in high yields under mild, and catalyst-free conditions using polyethylene glycol (PEG-400) as a solvent. The use of low cost PEG-400 makes it simple, convenient, and environmentally benign. [Copyright &y& Elsevier]

Abstract: Triazole moiety is frequently employed in drug discovery and optimization. However, most syntheses of triazole drugs involve isolation of highly explosive azides. Herein we report safe and high efficient syntheses of triazole drugs in aqueous/organic solvent systems with Cu2O nanoparticle (Cu2O-NP) as the catalyst of azide–alkyne cycloaddition (CuAAC). Since Cu2O-NP can be efficiently dispensed in aqueous and some organic solvents, the azide solutions from the previous preparation could be used directly in the next CuAAC stage without isolation. Therefore, this synthetic strategy is safe, convenient, and high yielding for the syntheses of triazole drugs. [Copyright &y& Elsevier]

Abstract: An efficient coupling of 2-hydroxychalcones/α,β-enones with 4-hydroxycoumarin/5,5-dimethylcyclohexyl-1,3-dione (dimedone) has been accomplished to provide access to a novel class of potential anticoagulants with 2,8-dioxabicyclo[3.3.1]nonane core. The reaction proceeds by Michael-bicycloketalization sequence under iodine catalysis (10mol%) in aqueous ethanol under reflux. Good to excellent yields, impressive selectivity, absence of byproduct formation, avoidance of toxic organic solvents, and utilization of metal-free water-compatible mild Lewis acid catalyst are the key attractive features of this protocol. [Copyright &y& Elsevier]

Abstract: New well-defined monodisperse oligocarbazoles-functionalized anthracenes An-OCZn (n =1, 2, 3) have been synthesized through Suzuki cross-coupling reaction of the brominated oligocarbazoles and 9,10-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)anthracene. They show good solubility in organic solvents, including dichloromethane, chloroform, toluene, ethyl acetate, and tetrahydrofuran. It should be noted that, in the case of An-OCZn, the formation of the excimer based on anthracene unit is suppressed completely due to the introduction of oligocarbazoles in 9,10-position of anthracene so that an intense blue-emitting has been afforded. In addition, the obtained An-OCZn exhibit good electrochemical and thermal stabilities. Thus, the oligocarbazoles-functionalized anthracenes can be a class of promising candidates for novel blue-emitting materials employed in OLEDs or related devices. [Copyright &y& Elsevier]

Abstract: We report efficient miniaturized conditions to prepare arrays of bicyclic lactams for screening. The nature of the solvent is usually an important factor of reactivity. At a small synthesis scale, when automated pipetting devices are required, physical properties of the solvent, such as surface tension and vapor pressure also become very important. After having shown that a complete evaporation of a solution of reagents in water or a mixture of ethanol and water yields the expected lactams, we exemplified the reaction and procedure with the preparation of a library of 80 members. Our synthesis scheme is validated for synthesis scales from 1 to 100mg. Therefore, it can be used both to produce rapidly test samples for HTS as well as to prepare intermediates for the synthesis of more elaborated nature-inspired compounds. [Copyright &y& Elsevier]

Abstract: Three new tetraphenylethylene based oligomers bearing triphenylethylene moiety were synthesized utilizing Suzuki coupling reaction and their aggregation-induced emission properties were studied. They show excellent solubility in common organic solvents and emit light in blue region (440−504nm). AIE effect is predominant for tetra-substituted TPE (20.1-fold) than mono-substituted one (4.5-fold). [Copyright &y& Elsevier]

Abstract: A method for the preparation of aryl trihalomethyl sulfones—active biocidal agents—with identical or different halogens is presented. The synthesis is based on the reaction of aryl methyl, aryl halomethyl, or aryl nitromethyl sulfones with sodium hypohalite. The method is simple in implementation, does not necessarily require the use of organic solvents, and selectively affords the products in good to excellent yields. Notably, it allows the preparation of the hitherto unknown phenyl trihalomethyl sulfone with three different halogens: fluorine, chlorine, and bromine. [Copyright &y& Elsevier]

Abstract: An ultrasound promoted easy, efficient, and environment friendly process has been devised for the synthesis of α-aminophosphonates within seconds through a one-pot three-component condensation of the aldehydes, amines, and triethylphosphite. The desired products were obtained in excellent yields and in high purity under solvent-free and catalyst-free conditions. Study with various aldehydes and amines reveals that ultrasound radiation plays a key role in the direct synthesis of α-aminophosphonates. [Copyright &y& Elsevier]

Abstract: The unprecedented nucleophilic tribromomethylation of N-(tert-butanesulfinyl)imines with bromoform has been shown to be a highly stereoselective and practical method for the synthesis of enantiomerically pure α-tribromomethyl amines. THF has proven to be the best solvent in this addition reaction. By changing the reaction solvent from THF to DMF, 2,2-dibromoaziridines can also be synthesized directly from bromoform and N-(tert-butanesulfinyl)imines under similar reaction conditions. [Copyright &y& Elsevier]

Abstract: Dry organic solvents are used for various organic reactions that employ moisture sensitive reagents. The processes to dry these solvents are hazardous and costly. Setting up reactions in an open atmosphere while using moisture sensitive reagents has little to no effect on the rate or yield of the reaction under mechanochemical conditions. We believe this is partly due to the gaseous nature of the water vapor in the air compared to the dissolved water and oxygen in solution. [Copyright &y& Elsevier]

Abstract: We have developed an efficient one-pot, two-step reaction protocol for the synthesis of eight-membered 1,5-benzodiazocine-2-ones by Ugi four-center three-component coupling reaction (U-4C-3CR) and subsequent reductive cyclization using Fe/NH4Cl in protic solvent. [Copyright &y& Elsevier]

Abstract: The improved preparation of 1-substituted-β-carbolines is reported using microwave-assisted aza-Wittig/electrocyclic ring-closure reaction with ionic liquids as solvent. In all cases an unprecedented N-methoxymethyl group (MOM) deprotection is observed. [Copyright &y& Elsevier]

Abstract: Modified nucleobases and nucleic acids have found many biological and pharmaceutical applications. Here we report a microwave-directed synthesis of a variety of modified uracil and cytosine nucleobases with high yields under solvent-free conditions. The reaction yields were further improved by addition of Lewis acid. The crystal structures of 5-isopropyl-6-methyluracil and 6-phenyluracil were also determined. [Copyright &y& Elsevier]

Abstract: This work reports the synthesis of new fatty N-acylamino acids and N-acylamino esters from the C16:0, C18:0, C18:1, and C18:1(OH) fatty acid families and demonstrates the activity of these compounds as organogel agents. Compounds were heated and dissolved in various solvents (n-hexane, toluene, and gasoline). Only saturated C16:0 and C18:0 derived from alanine were able to form gels in toluene, and saturated C16:0 derived from phenylalanine showed gelation in n-hexane. This is the first evidence that fatty N-acylamino esters and N-acylamino acid derivatives of l-serine and fatty acids C16:0, C18:0, and C18:1 are able to form gels with hexane. This observation confirms the importance of the hydroxyl group in the segment derivative of l-serine in forming good gels. [Copyright &y& Elsevier]

Abstract: A series of trifluoromethylated cyclopenta[b]pyran derivatives were synthesized efficiently from 1,3-cyclopentanedione, arylaldehydes, and ethyl 4,4,4-trifluoro-3-oxobutanoate via one-pot multi-component reaction catalyzed by NH4OAc. This one-pot multi-component process comprises an initial Michael addition and a subsequent intramolecular cyclization reaction. The effect of catalysts and solvents on the reaction efficiency and the yield were investigated. The structure of product 4f was further confirmed by XRD analysis. Meanwhile, further transformation of hemi-ketal moiety to the corresponding dehydrated product is also studied. In addition, a possible mechanism of this reaction is proposed herein. [Copyright &y& Elsevier]