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A mild and inexpensive method of alkylation of pyrrole and indole with substituted 4chromanols and 3‐arylidene‐4‐chromanols mediated by montmorillonite K‐10 is reported. Indole and pyrrole upon treatment with 4‐chromanols in the presence of activated montmorillonite K‐10 undergo facile nucleophilic substitution under ambient condition to afford 2‐(chroman‐4‐yl)‐1H‐pyrrole and 3‐(chroman‐4‐yl)‐1H‐indole in moderate to good yields. In the case of 3‐arylidene‐4‐chromanols, this direct dehydrative substitution reaction is found to be highly regioselective affording only the respective C‐4 substituted (arylidene‐chroman‐4‐yl)‐ pyrrole/indole derivatives. [ABSTRACT FROM AUTHOR]

Immobilization of enzymes from different sources on various supports in designed systems increases enzymes' stability by protecting the active site of it from undesired effect of reaction environment. Also, immobilization decreases the cost of separation and facilities the reuse of the enzymes. Therefore, the design of new immobilization enzyme preparations has been an inevitable area of modern biotechnology. Herein, Rhizomucor miehei lipase (RML) was immobilized on montmorillonite K-10 (MMT-RML) by adsorption and in polyvinyl alcohol (PVA-RML) by entrapment to obtain a more stable and active lipase preparation. The free and immobilized lipase preparations were characterized for p-nitrophenyl palmitate hydrolysis. The apparent Michaelis–Menten (Kmapp) constant was almost the same for the free RML and PVA-RML, whereas the corresponding value was 17.7-fold lower for MMT-RML. PVA-RML and MMT-RML have shown a 1.1 and 23.8 folds higher catalytic efficiency, respectively, than that of the free RML. The half-lives of PVA-RML and MMT-RML were found to be 7.4 and 3.4 times longer than the free RML at 35 °C, respectively. PVA-RML and MMT-RML maintained 65% and 87% of their initial activities after four reuses. These results showed that the catalytic performance of RML has improved significantly by immobilization. [ABSTRACT FROM AUTHOR]

• Selective isocyanate recovery from PUs using MK10 is found impractical. • High MK10 amounts destroy the formed phenyl isocyanate, yielding the side product diphenylurea. • Isocyanate yields from methyl phenyl carbamate never exceed 30 %. • MK10 appears to chemisorb isocyanate, most likely as a carbamate. The significant growth of the production and use of flexible polyurethane (PU) foam causes increased waste accumulation, thereby creating a demand for the recycling of PU. While upgrading PU materials to recycled polyols has been studied in detail, the recovery of diisocyanates is a longstanding challenge. Montmorillonite K10 (MK10) has been proposed as a catalyst to convert carbamates into isocyanates, but its prospects are unclear. Here, the MK10-catalyzed decomposition of methyl phenylcarbamate (MPC) into phenylisocyanate (PI) and the side product N,N' -diphenylurea (DPU) has been studied as a model reaction for the decomposition of PU foam and the potential recovery of PI. The effects of the amount of catalyst, the temperature, and the solvent were investigated by HPLC analyses. Kinetic analysis revealed that the uncatalyzed rate of the MPC decomposition is much lower than the catalyzed rate, indicating that the thermally driven decomposition is negligible. Our results, involving both experimental kinetic studies and models of the kinetics, show that, while MK10 effectively catalyzes the decomposition of MPC, it also causes the formation of aniline, which reacts with PI to form DPU. As a result, large amounts of MK10 favor DPU and prevent the selective formation of PI, and yields of PI >30 % were never observed. Likely, the OH groups of MK10 form covalent bonds with PI, causing a deficiency in the mole balance. Overall, MK10 is unsuited to provide high yields of isocyanates. The experimental studies and kinetic models in this research demonstrate that MK10 not only activates the conversion of carbamates into isocyanates, but also stimulates the (undesired) formation of ureas and the binding of isocyanates to the OH groups of the catalyst. [Display omitted] [ABSTRACT FROM AUTHOR]

An efficient one-pot protocol for the synthesis of 2-((substituted amino)(4-phenyl)methyl)-3-hydroxy-naphthalene-1,4-dione derivatives has been developed by the three-component reaction of 2-hydroxy-naphthalene-1,4-dione, aromatic aldehydes and anilines/heterocyclic amines using montmorillonite K-10 as a catalyst. The advantages of this method include short reaction time, excellent yield and easy work-up. [ABSTRACT FROM AUTHOR]

Esterification of acetic acid with sec-butanol to produce sec-butyl acetate has been systematically carried out by using mesoporous (3-9 nm size) aluminosilicate (meso-AS) catalysts (surface area 327-578 m g) derived from Na-montmorillonite by controlled HCl acid activation. High catalytic activity up to 89% conversion with nearly 100% selectivity towards sec-butyl acetate is observed. The effect of reaction temperature, mole ratio of reactants and catalyst concentration on esterification reactions were studied. The catalyst could be recycled and reused several times without significant loss of their catalytic activities. The catalysts were characterized by pyridine adsorbed FT-IR, XRD, SEM-EDX, MAS-NMR, surface area (BET) and TPD analysis. [ABSTRACT FROM AUTHOR]

Abstract: Preparation of palladium nanoparticles supported on montmorillonite K‐10 clay is described. The utility of thus prepared catalyst was examined for copper free acyl Sonogashira reaction of acid chlorides with phenyl acetylenes to achieve various ynone scaffolds. Coumarin derived ynones were also synthesized under mild optimized reaction conditions. All the title compounds were obtained in good to excellent yield. The recycling efficiency of the catalyst was extremely good and used successfully for seven cycles without significant drop in the yield. [ABSTRACT FROM AUTHOR]

Twelve 4-aryl-3,4-dihydrocoumarins were synthesized by the condensation of phenols with the corresponding substituted cinnamic acids in the presence of nitrobenzene and sulfated montmorillonite K-10. This method displayed the property of green chemistry with respect of reuse of the catalyst. These compounds were evaluated for hydroxyl radical scavenging activity in vitro. Results showed that compounds with 7,8-dihydroxy groups had relatively strong hydroxyl radical scavenging activity. [ABSTRACT FROM AUTHOR]

Novel 2,3-dihydro-4-pyridinones were synthesized via the reaction of curcumin and primary amines or amine acetates under microwave irradiation. Montmorillonite K-10 was used as a catalyst. Reaction times did not exceed 120 s. The structures of the compounds were established by elemental analysis and from their mass, 1H- and 13C-NMR spectra.

The extraction of phenolic compounds from biomass is an important way to replace chemical synthesis techniques, and catalytic pyrolysis of biomass is an effective method to obtain phenolic compounds with high selectivity. In this work, cobalt-modified montmorillonite K-10(CMT) catalyst was prepared by using cobalt salt and montmorillonite K-10(MMT), and used to catalyze the pyrolysis of corn stalk(CS) to produce phenol-rich bio-oil. The catalytic pyrolysis characteristics reflected by the liquid and gaseous components were compared using gas chromatography-mass spectrometry(GC-MS) and online mass spectrometry(online MS), and the catalytic pyrolysis behavior of corn stalk was analyzed by using the thermogravimetric analyzer(TGA). The addition of catalyst resulted in the increase of apparent activation energy of pyrolysis process but increased selectivity for phenolic compounds. Compared with the blank sample, the relative content of phenolic compounds in bio-oil increased by 11.99 %, and the selectivity of alkyl-phenols was stronger. In addition, the results also showed that the synthesized catalyst promoted the production of H 2 and CH 4 during the catalytic pyrolysis. The optimum ratio of the prepared catalyst was 6%Co/15%MMT. These works provide an alternative approach to upgrading bio-oil product. • A catalyst that effectively improves the selectivity of phenols is synthesized. • A 11.99 % increase in phenols is obtained by adding 6%Co/15%MMT catalyst. • The reforming of oxygenates to form phenolic compounds is enhanced. • A pathway for producing phenols via biomass catalytic pyrolysis is presented. [ABSTRACT FROM AUTHOR]

The syntheses of cis-3a,4,7,7a-tetrahydroisoindole-1,3-dione derivatives and some cyclic diimides were performed by the reaction of different aromatic and aliphatic amines and diamines with cis-1,2,3,6-tetrahydrophthalic anhydride and maleic anhydride on montmorillonite K-10 under microwave irradiation and solvent- free conditions. The desired attractive products were obtained in high yields and characterized by elemental analysis aswell as by IR and 1H-NMR spectroscopy.

The preparation of beta-enamino ketones and esters using the methodology of the reactions on solid support coupled with microwave irradiation is described. The reaction of cyclic, acyclic and alpha-chloro-substituted beta-dicarbonyl compounds with amines or their corresponding ammonium acetates was carried out using K-10 as solid support and a domestic microwave oven as the radiation source to give beta-enamino carbonylic compounds in good yields.

The microwave promoted reaction of warfarin with methanol, or ethanol, in the presence of montmorillonite clay K-10 as a catalyst, affords the corresponding acetals, 2-methoxy-2-methyl-4-phenyl-3,4-dihydro-2H-pyrano[3,2-c]chromen-5-one (2) and 2-ethoxy-2-methyl-4-phenyl-3,4-dihydro-2H-pyrano[3,2-c]chromen-5-one (3), respectively, in good yields.

The microwave promoted reaction of warfarin with methanol, or ethanol, in the presence of montmorillonite clay K-10 as a catalyst, affords the corresponding acetals, 2-methoxy 2-methyl-4-phenyl-3,4-dihydro-2H-pyrano[3,2-c]chromen-5-one (2) and 2-ethoxy-2-methyl- 4-phenyl-3,4-dihydro-2H-pyrano[3,2-c]chromen-5-one (3) respectively, in good yields.

The reaction of a series of 1-tetralones with thallium trinitrate supported on Montmorillonite K-10 clay led to products of ring contraction (methyl indan-1-carboxylates) and/or alpha-oxidation (2-methoxy-1-tetralones), in variable yields.

Simple and eco-friendly synthesis of 2-substituted benzothiazoles is described. The reaction is performed in absolute ethanol at room temperature, using a catalytic amount of montmorillonite K-10, and with continuous bubbling of air as oxidant. Simplicity, ease of handling of the system, an environmentally friendly and reusable catalyst, a plentiful, inexpensive, and safe oxidant, and mild conditions are the main advantages of this procedure. [ABSTRACT FROM AUTHOR]

Microwave-assisted montmorillonite K-10-catalyzed Friedlander synthesis of quinolinylquinolinones has been developed. The efficient and eco-friendly catalyst along with the convenience of the product isolation make this process an attractive alternative for the synthesis of target heterocycles. The synthesized products were confirmed by FTIR, H NMR, C NMR, and mass spectroscopic techniques. All the synthesized compounds showed good antibacterial property similar to standard Ampicillin and enhanced antioxidant activity. [ABSTRACT FROM AUTHOR]

An efficient transition-metal-free synthetic method of 1 H -indazoles has been developed. The reaction of arylhydrazones in the presence of montmorillonite K-10 in 1,2-dichlorobenzene at 130 °C afforded 1 H -indazoles in good yields most likely via a sequential intramolecular nucleophilic cyclization and an aerobic oxidation pathway. [ABSTRACT FROM AUTHOR]

A short and efficient methodology for the synthesis of chiral dioxa-caged compounds from levoglucosenone, a biomass-derived enone, is herein presented. The key transformation, that involves a cascade 3-step cationic cyclization, was efficiently carried out in high yields and selectivities by Montmorillonite K-10 catalysis. The usefulness of K-10 in related semi-pinacol rearrangements to obtain pyran-3-ones is also shown. Interesting differences in the reactivity pattern was found for epimeric alcohols, and the origins of these findings were determined by DFT calculations. [ABSTRACT FROM AUTHOR]

An efficient synthetic route to isoxazoline fused carbocycles from carbohydrate scaffolds that comprise of free hydroxyl group(s) is described with high regio- and stereoselectivity. Montmorillonite K-10/chloramine T oxidation and in situ intramolecular nitrile oxide–alkene cycloaddition (INOC) of d -ribose derived oximes have been developed for the diversity oriented synthesis of isoxazoline fused five and six membered carbocycles. [ABSTRACT FROM AUTHOR]

A simple and mild procedure for the synthesis of different naphthopyrans providing high yields in a short reaction time was reported. The reaction of propargylic alcohols with α- or β-naphthol and dihydroxy naphthalenes in the presence of montmorillonite K-10 was studied. This reaction afforded high yields of the corresponding naphthopyrans. In addition, a number of new phenylene and biphenylen-linked bisnaphthopyrans were synthesized providing excellent yields via the one-pot reaction of bis-propargyl alcohols with β-naphthol. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Highlights: [•] Lipase was immobilized onto montmorillonite via adsorption and covalent binding. [•] The immobilized enzymes displayed enhanced catalytic efficiency and storage stability. [•] The activity of the free lipase in heptane was 0.51% of that in the aqueous medium. [•] The organomodified nanoclays would be suitable for industrial biotransformations. [Copyright &y& Elsevier]

The rapid and highly efficient synthesis of 5,5-disubstituted hydantoins achieved by three-component condensation of corresponding ketones and aldehydes, potassium cyanide and ammonium carbonate in an additional reaction under ultrasound irradiation by using montmorillonite K-10 as a heterogenous catalyst. Utilizing ultrasound irradiation and montmorillonite in this method has several benefits, for example short reaction time, high yield and use of recyclable catalyst. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Highlights: [•] Diglycerol synthesis via solvent-free glycerol etherification. [•] LiOH modification of acid-treated montmorillonite K-10. [•] Elucidation of surface physicochemical properties. [•] High diglycerol selectivity of 53% at 98% conversion. [•] Improved selectivity of αβ diglycerol isomer with reduced αα isomers. [Copyright &y& Elsevier]

Abstract: Rhodium (0) nanoparticles were generated in the nanopores of Montmorillonite K-10 clay by reduction of RhCl3·3H2O impregnated clay with NaBH4. Pore size of the clay and hence the size of Rh nanoparticle was controlled by choosing <2μm fraction of the clay as catalyst support. TEM/HRTEM/SAED images confirmed the growth of well dispersed spherical Rh (0) nanoparticles in 1–3nm diameter range having face centred cubic lattice with inter-planar lattice fringe spacing of 0.23nm corresponding to [111] planes. XPS analysis confirmed the presence of Rh metal in zero oxidation state and absence of other oxidation states of Rh. BET surface area determination through N 2 adsorption–desorption isotherm revealed decrease in surface area of the clay support from 298m2/g to 196.4m2/g after incorporation of Rh (0) nanoparticles. The Rh (0) nanoparticles supported clay is proved to be highly active and selective heterogeneous catalyst for hydrogenation of monoterpenes (geraniol, limonene, β-pinene, citronellal and linalool) at ambient temperature and pressure (1–4bar). The number of active sites was calculated using surface statistics and adopting model for full shell clusters. Turnover frequency (TOF) calculations for the catalyst gave encouraging results. [Copyright &y& Elsevier]

Abstract: Acid treated montmorillonite K-10 (MK-10) was intercalated with LiOH (Li/MK-10) to catalyze selective production of diglycerol via solvent free glycerol etherification reaction. The structure, surface properties and basic strength of parent and modified clay were successfully characterized using XRD, SEM, ICP, BET surface analyzer and Hammett indicators to elucidate their physical and chemical properties. The glycerol etherification reaction was conducted at 240°C with 2wt.% lithium intercalated catalyst under inert atmosphere. High diglycerol selectivity of about 53% was obtained in 12h with this catalyst at a glycerol conversion of about 98%. [Copyright &y& Elsevier]

Abstract: Montmorillonite K-10 mediated MCR of anilines, arylaldehydes and ethyl-3,3-diethoxypropionate in water afforded 2,6-unsubstituted dihydropyridines depending on the nature of anilines employed. A variety of dihydropyridines were prepared by using this green methodology in good yields and montmorillonite K-10 was found to be an inexpensive and reusable catalyst. The structure elaboration of a representative compound was carried out under Heck conditions. Some of the compounds synthesized showed significant inhibition of PDE4B when tested in vitro. Docking studies indicated that one of the ester moieties of these compounds played a key role in their interactions with the PDE4B protein. [Copyright &y& Elsevier]

A successful aza- Michael addition of arylamines to a conjugated enone, acryloylferrocene, has been achieved by ultrasonic irradiation of the mixture of these reactants and the catalyst, i.e., montmorillonite K-10. This solvent-free reaction, yielding ferrocene containing Mannich bases, 3-(arylamino)-1-ferrocenylpropan-1-ones, considered as valuable precursors in organic synthesis, has been performed by using a simple ultrasonic cleaner. Among 17 synthesized β-amino ketones, three were new ones, and these were fully characterized by spectroscopic means. X-Ray crystallographic analysis of three of these crystalline products enabled the insight into the conformational details of these compounds. All compounds were evaluated for their antibacterial activities against six Gram-positive and five Gram-negative strains in a microdilution assay. The observed promising antibacterial activity (with a MIC value of 25 μg/ml ( ca. 0.07 μmol/ml) as the best result for almost all tested compounds against Micrococcus flavus) seems not only to be compound but also bacterial species-specific. [ABSTRACT FROM AUTHOR]

A microwave-assisted montmorillonite K-10 catalyzed synthesis of pyrrolocoumarins and pyrroloquinolones from acetylenic amine is described. The reaction utilizes montmorillonite K-10 as an inexpensive, recyclable, and environmentally benign acid catalyst. Reactions were completed in few minutes under microwave irradiation and provided excellent yields. The efficient and ecofriendly catalyst and the convenience of the product isolation make the process an attractive alternative for the synthesis of these important heterocycles. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and green synthesis of functionalized cyano pyridines has been achieved via montmorillonite K-10 mediated multi-component reaction in a chemo- and regioselective manner. The four-component reaction of β-keto ester, arylaldehyde, malononitrile and an alcohol provided a variety of pyridine derivatives and montmorillonite K-10 was found to be a reusable catalyst. The potential of this operationally simple methodology has been demonstrated in further structure elaboration of a compound synthesized via C–C bond forming reactions under Suzuki, Sonogashira and Heck conditions. Some of the cyano pyridines synthesized showed PDE4B inhibitory properties in vitro and good interactions with PDE4B protein in silico suggesting cyano pyridine scaffold as a potential template for the discovery of novel PDE4 inhibitors. [Copyright &y& Elsevier]

Abstract: Syntheses of fourteen new 3-(arylamino)-1-ferrocenylpropan-1-ones have been achieved in good to excellent yields by an aza-Michael addition of different arylamines to acryloylferrocene. The reaction was performed by microwave (MW) irradiation (500W/5min) of a mixture of reactants and montmorillonite K-10, without a solvent. The obtained compounds were spectrally and electrochemically (cyclic voltammetry) fully characterized, whereas single-crystal X-ray analysis has been performed for three of them. In a microdilution assay, all of the compounds were shown to have a broad-spectrum effect on Gram-negative and -positive bacteria, although the degree of inhibition varied. A notable activity was observed for all compounds in inhibiting the growth of an important human pathogen Staphylococcus aureus. [Copyright &y& Elsevier]

n efficient and environmentally benign one-pot method for the synthesis of 1-methyl-2,6-diarylpiperidin-4-ones using montmorillonite K-10 as a catalyst has been developed. Antimicrobial activity of the compounds has been tested against selected representatives of Gram-positive and Gram-negative bacteria and fungi. [ABSTRACT FROM AUTHOR]

Abstract: Montmorillonite K-10 clay-catalyzed substitution reactions of 3,4,6-tri-O-alkyl-2-C-hydroxymethyl-d-glycals, 3,4,6-tri-O-acetyl-d-glycals, 3,4,6-tri-O-alkyl-d-glycals, and 3,4-(dihydro-2H-pyran-5-yl)methanol with a few alcohols and phenols are described. The reactions of 2-C-hydroxymethyl-d-glycals with phenols were similar to those of 2-C-acetoxymethyl-d-glycals and afforded pyrano[2,3-b]benzopyrans. This montmorillonite K-10 clay-catalyzed transformation is facile both under ambient (Method 1) and microwave conditions (Method 2). Ferrier rearrangement of 3,4-(dihydro-2H-pyran-5-yl)methanol with p-cresol, 2,6-xylenol, and ethanol led to totally unexpected transformations. Reaction of 2-C-hydroxymethyl-d-galactal with 2,6-dimethylphenol in the presence of montmorillonite K-10 led to a novel domino transformation affording 4-(5′,6′-dihydro-4H-pyran-3′-ylmethyl)-2,6-dimethylphenol. In contrast, 3,4,6-tri-O-acetyl-d-glucal furnished the Ferrier rearrangement product, 2,6-dimethylphenyl 4,6-di-O-acetyl-2,3-dideoxy-α-d-erythro-hex-2-enopyranoside. Also, isomerization of 3,4,6-tri-O-alkyl-d-glycals to products of allylic rearrangement, 2,3-unsaturated-O-glycosides in good yields is reported. [Copyright &y& Elsevier]

Novel 2,3-dihydro-4-pyridinones were synthesized via the reaction of curcumin and primary amines or amine acetates under microwave irradiation. Montmorillonite K-10 was used as a catalyst. Reaction times did not exceed 120 s. The structures of the compounds were established by elemental analysis and from their mass, ¹H- and 13C-NMR spectra. [ABSTRACT FROM AUTHOR]

Abstract: An environmentally benign protocol has been described for the synthesis of novel 2-(1′,3′-dihydro-1H-[2,3′]biindolyl-2′-ylidene)-indan-1,3-diones/bis-indolylindane-1,3-diones from ninhydrin and 3-substituted/unsubstituted indoles. It uses montmorillonite K-10 as catalyst in a solvent-free condition under microwave irradiation. The method was also used for the synthesis of novel bisindolylindeno[1,2-b]quinoxaline derivatives. [Copyright &y& Elsevier]

A new solid acid-catalyzed method was developed for the stereoselective preparation of cis-aziridines from imines and ethyl diazoacetate using montmorillonite K-10 as catalyst. The �reactions proceeded readily at room temperature in short reaction times, providing the products in excellent yields (90%) and exclusive selectivity. [ABSTRACT FROM AUTHOR]

Abstract: A microwave-assisted solid acid-catalyzed synthesis of quinolines from anilines and cinnamaldehydes is described. Use of montmorillonite K-10 results in a one-pot process; the cyclization and oxidation steps readily take place in a domino approach. Reactions were completed in a matter of minutes and provided excellent yields. The efficient and ecofriendly catalyst and the convenience of the product isolation make this process an attractive alternative for the synthesis of these important heterocycles. [Copyright &y& Elsevier]

Abstract: A rapid, microwave-assisted synthesis of β-carbolines via a successive condensation/cyclization/dehydrogenation approach is described. This methodology involves the coupling of various tryptamines with aromatic aldehydes/glyoxals. The product imine undergoes a Pictet–Spengler cyclization followed by a final dehydrogenation to yield β-carbolines in a three-step domino reaction. The use of the bifunctional catalyst Pd/C/K-10 combined with microwave irradiation enabled the synthesis of β-carbolines in short reaction times and in good to excellent yields. [Copyright &y& Elsevier]

Abstract: It has been found that SbCl3 supported on montmorillonite K-10 is an efficient and reusable catalyst for Friedel–Crafts alkylation of nitrogen heterocycles such as indoles and pyrroles with epoxides. The reaction gives the corresponding C-alkylated derivatives in good to excellent yields with a high regioselectivity. [Copyright &y& Elsevier]

The series of AB ring cores of mappicine 5a-e were generated by the reaction of 2-chloro-quinoline-3-carbaldehyde 4a-e with NaBH4 through eco-friendly route. All the synthons were characterized by FTIR, ¹H-NMR, 13C-NMR, LCMS and HRMS techniques. All the synthesized compounds were screened for their antioxidant activity, in vitro hemolytic activity, on human erythrocytes and cytotoxicity, on HeLa and Vero cells. Out of all synthons, 5e exhibit good antioxidant as well as cytotoxicity activities, where 5d showed promising hemolytic activity, and compound 5a (2-chloro-quinolin-3-yl)-methanol displayed good cytotoxicity with noteworthy selectivity towards HeLa cells. [ABSTRACT FROM AUTHOR]

Regioselective acylation of enaminones in the presence of catalysts such as nickel acetylacetonate [Ni(acac)2] and montmorillonite K-10 to give C-allylated products is reported. Nickel acetylacetonate [Ni(acac)2] complexes of β-enamino compounds react with electrophiles as phenyl isocyanate and isothiocyanate at methin carbon, in good to excellent yields. [ABSTRACT FROM AUTHOR]

Solvent-free syntheses of quinazolin-4(3H)-ones were performed by reaction of anthranillic acid with different amides, such as nicotinamide, benzamide, formamide, etc., on montmorillonite K-10. Products were confirmed by FTIR, 1HNMR, and 13CNMR spectroscopic techniques. All synthesized compounds exhibited antioxidant properties and have been compared with standard antioxidant BHT. [ABSTRACT FROM AUTHOR]

Abstract: A new, solid acid-catalyzed microwave-assisted environmentally benign synthesis of isobenzofuran-1(3H)-ones is described. Montmorillonite K-10 appeared to be an excellent catalyst for the condensation and successive lactonization reactions. Reaction of phthalaldehydic acid (2-carboxybenzaldehyde) with methylaryl and cyclic ketones was initiated by microwave irradiation and occurred in one step. The reactions were complete in 10–30 minutes providing excellent yields (90–98%). [Copyright &y& Elsevier]

Montmorillonite K-10-catalyzed Fischer type glycosylation was studied for various monosacharides with different alcohols under microwave irradiation. The method was found to be efficient, economic, simple, and time saving and the catalyst montmorillonite K-10 was reused three times without loss of catalytic activity and anomeric selectivity. With glycerol, the method gave products glycosylated at primary alcohols only. [ABSTRACT FROM AUTHOR]