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A simple and highly efficient approach to the synthesis of bis(naphthol)methane (BNM) and bis(indolyl)methane (BIM) derivatives has been developed. In the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO)-based ionic liquid catalysts, which are environmental friendly, inexpensive, and recyclable, the reaction afforded the corresponding products in good to excellent yields within short times under solvent-free conditions. The catalysts can be easily recovered and reused several times without significant loss in activity. [ABSTRACT FROM AUTHOR]

A new and versatile synthetic approach towards bis(pyr-azolyl)methanes, based on 1,4-addition of pyrazoles to conjugated α-halogenated nitroso- and azoalkenes, is described. Tris(pyra-zolyl)methanes can also be obtained by this methodology. [ABSTRACT FROM AUTHOR]

An efficient approach to the benzylation of arenes has been developed. The reactions described provide straightforward access to diarylmethanes through Pd-catalyzed coupling of benzylic phosphates with arylsilanes in good to excellent yields. The reaction tolerates a wide range of functionalities such as halide, alkoxyl, and nitro groups. [ABSTRACT FROM AUTHOR]

Bis(iodozincio)methane, prepared from diiodomethane and zinc metal in the presence of a lead catalyst, is capable of performing several unique molecular transformations. It can operate not only as a dianion, but also as a bidentate Lewis acid. In this account, the methylenation of carbonyl compounds, nucleophilic cyclopropanation reactions, 1,4-addition reactions of bis(iodozincio)methane, and reduction reactions of n-allylpalladium are discussed, along with the associated density functional theory calculations. 1 Introduction 2 Methylenation of Carbonyl Compounds 3 Nucleophilic Cyclopropanation 3.1 Cyclopropanation of 1,2-Diketones 3.2 Asymmetric Construction of Quaternary Carbon Atoms by Stereospecific Cyclopropanation 4.1,4-Addition Reactions of Bis(iodozincio)methane 4.1 Three-Atom Ring-Contraction Reaction 4.2 Enolate-Homoenolate Intermediates and Their Reactions 5 Reduction of n-Allylpalladium Derivatives 6 Conclusions and Outlook [ABSTRACT FROM AUTHOR]

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]