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Herein we report the multicomponent synthesis of the bis(indolyl)methane derivatives in a ball mill. The reaction was carried out under solvent-free conditions using only the Lewis acid-surfactant-SiO2 composite nanocatalyst (LASSC) prepared in situ. The unsymmetrical bis(indolyl) methane derivatives containing nitro or fluorine substitution with a yield of 72%–92% were obtained in a short reaction time. Within we verified that under the action of the combined catalyst of AlCl3·6H2O + SDS + SiO2, the method of preparing unsymmetrical bis(indolyl)methane by mechanical grinding without solvent has obvious advantages. Finally, we inspected that the catalysis system can be used eight times without a significant decrease in activity. [ABSTRACT FROM AUTHOR]

This study used aryl diazonium salts as catalysts to catalyze reductive aminations of carbonyls and the synthesis of bis (3-indolyl)methane derivatives. The catalytic system showed good tolerance to substituents in the substrate in these two reactions. The separation yields of reductive aminations range from moderate to excellent. The separation yield of the reaction for synthesizing bis(3-indolyl)methane derivatives ranges from good to excellent. Finally, we also explored the catalytic behavior of aryl diazonium salts in amination reduction reactions. [Display omitted] [ABSTRACT FROM AUTHOR]

The immobilization of AlCl3, an extremely hygroscopic Lewis acid, on graphene oxide as a support material with a high surface area was studied. The obtained solid material was characterized by FTIR spectroscopy, TGA/DTA analysis, field emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy and used as an efficient and bench-top environmentally benign catalyst for the preparation of bis (pyrazolyl)methane derivatives through the condensation of aldehydes and 3-methyl-l-phenylpyrazol-5-one. The catalyst is reusable for at least nine times with a negligible loss in its catalytic activity. [ABSTRACT FROM AUTHOR]

A PIV study of a conical premixed methane-air Bunsen flame has shown that the inside of the cone has a complex gas-dynamic structure. In this system, the velocity of the gas flow entering the flame front varies in different parts of the flame cone and the stream tubes are not straight. The Landau-Markstein effect is discussed in the interpretation of the experimental data. A method of processing PIV measurement results is proposed that improves the accuracy of determining the burning velocity and allows a quantitative determination of the catalytic effect of submicron TiO particles, which is proportional to the particle surface area. The relative increase in the burning velocity is 2% per each ≈0.01 cm/cm (particle surface/gas volume) of the total specific surface area of the particles. The experimental data are well described by modeling using well-known literature data on the detailed mechanism of chemical reactions and the mechanism of catalytic oxidation of methane with oxygen on metal oxides. [ABSTRACT FROM AUTHOR]

Highlights: [•] Regioselectivity for either the 3- or the 2-hydroxyl group of a manno-pyranoside. [•] Catalyst concentration dependence of selectivity. [•] Different diaryldiazomethanes give different regioselectivity. [Copyright &y& Elsevier]

Biologically important bisindolylmethanes are synthesized in a domino fashion by using an iron(II) chloride-(±)-1,1'-binaphthyl- 2,2'-diamine [FeCl2-(±)-BINAM] complex as the catalyst. This method proceeds via oxidation of a primary alcohol into the corresponding aldehyde followed by nucleophilic addition of an indole in the presence of the catalyst. A reaction intermediate is synthesized separately and converted into the bisindolylmethane product under the same reaction conditions as support for the proposed mechanism. [ABSTRACT FROM AUTHOR]

In this study, anthracenes were efficiently synthesized from o -alkynyldiarylmethane using a novel method that exploits the synergistic effect between Bi(OTf) 3 as the catalyst, and trifluoroacetic acid (TFA). Through this reaction, we achieved the rapid and efficient synthesis of anthracenes bearing various functional groups under mild conditions. [ABSTRACT FROM AUTHOR]

A series of bis(pyrazolyl)methane Cu complexes catalyze a fast Pd-free Sonogashira coupling reaction of iodo arenes with terminal alkynes. [ABSTRACT FROM AUTHOR]

The title compounds are prepared in modest to good yields from salicylaldehydes (I) and dichlorobenzylidenemethanes (II), (IV), and (VI). [ABSTRACT FROM AUTHOR]

The reaction of (II) with hetaryl bromides such as (VIIa,b) or 2- instead of 3-thiophene derivatives fails. [ABSTRACT FROM AUTHOR]

An asymmetric Pd-catalyzed [3 + 2] cycloaddition of alkynyl substituted trimethylenemethane donors is developed to allow the synthesis of highly functionalized cyclopentanes having three contiguous stereocenters. [ABSTRACT FROM AUTHOR]

A general method for the Pd-catalyzed allylic substitution with diarylmethane derivatives is reported. [ABSTRACT FROM AUTHOR]

This method is based on the use of aromatic sodium sulfinates as aryl sources, affording diarylmethanes in moderate to good yields via extrusion of SO2. [ABSTRACT FROM AUTHOR]