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Recent developments in task specifically functionalized imidazolium salts, which can be used for specific tasks ranging from catalysts recycling, supports for organic synthesis, catalysis, separation of specific metal ions from aqueous solution, and construction of nanostructures and ion conductive materials, have been reviewed.

Synergistic catalysis, a type of plural catalysis which utilizes at least two different catalysts to enable a reaction between two separately activated substrates, has unlocked a plethora of previously unattainable transformations and novel chemical reactivity. Despite the appreciable utility of synergistic catalysis, specific examples involving two transition metals have been limited, as ensuring a judicious choice of reaction parameters to prevent deactivation of catalysts, undesirable monocat

The catalyst reactivity and reusability for the lanthanide triflate-catalyzed three component synthesis of alpha-amino phosphonates have been examined in room temperature ionic liquids, [bmim][X], in which the catalytic activities were very dependent on the counter anion, X, as well as on the phosphorus nucleophile, and moreover, the catalyst immobilized in an ionic liquid was reused several times without any loss of activity.

Palladium nanoparticles have been deposited onto imidazolium bromide-functionalized ionic MWCNTs through hydrogen reduction of Na2PdCl4 in water without aid of surfactants under extremely mild conditions, and combined with an ionic liquid to create a new recyclable ionic liquid-based catalytic system allowing up to 50 times recycling.

Introduction of imidazolium ionic liquid pattern to the catalyst not only avoided catalyst leaching but also increased the stability of catalyst in ionic liquid, and thus, the Rh-complex of 1,4-bisphosphine bearing two imidazolium salt moieties was successfully immobilized in an ionic liquid and reused several times for the hydrogenation of an enamide without significant loss of catalytic efficiency.

[reaction: see text] Rh-Me-BDPMI (1a) complex can be an effective catalyst for the hydrogenations of (E)- and (Z)-beta-(acylamino)acrylates, in which the Z-isomers hydrogenated with the same or even higher ee values than the corresponding E-isomers. The conversion yield and enantioselectivity of E- and Z-isomers were largely dependent on the solvent, and thus, the E-isomers were hydrogenated more effectively in CH(2)Cl(2), whereas the Z-isomers were hydrogenated more effectively in polar MeOH so

Palladium nanoparticles were captured onto spherical silica particles using a molecular band composed of imidazolium chloride and urea moieties to form raspberry-like Pd@SiO2 composites, which can be recovered and reused without any loss of catalytic activity in Suzuki-Miyaura coupling.

The first "Off-On" type fluorescent probe for Au3+ is reported, in which rhodamine-alkyne derivative displayed highly selective fluorescence enhancement and "naked-eye" detection upon the addition of Au3+ at pH 7.4.

A straightforward route toward construction of α-quaternary chiral β-lactam moiety via Rh(II)/Pd(0)-catalyzed stereoselective relay catalytic reaction is reported. This asymmetric dual relay catalysis involves Rh(II)-catalyzed enantioselective intramoluecular C–H insertions of α-diazoamides, and sequential Pd(0)-catalyzed diastereoselective intermolecular allylic alkylation. Under mild reaction conditions, a broad range of α-quaternary allylated chiral β-lactams have been synthesized in high yie

Appropriate gauche steric interactions between the N-substituents and the phosphanylmethyl groups (see picture, top right) in the novel 1,4-diphosphane ligands 1 having an imidazolidin-2-one backbone affect the conformational flexibility of the seven-membered chelate ring formed by coordination to a metal atom. Thus, Rh complexes of 1 are excellent catalysts for enantioselective hydrogenation of enamides (bottom, cod=cyclooacta-1,5-diene). Supporting information for this article is available on

The Blaise reaction intermediate, a zinc bromide complex of beta-enamino ester, could be activated in situ by addition of a stoichiometric or catalytic amount of n-BuLi to allow chemoselective tandem C2-acylation providing alpha-acyl-beta-enamino esters, which are valuable intermediates for the syntheses of tri- and tetrasubstituted pyrazoles.

The catalytic activity of lanthanide triflates, particularly scandium triflate, increased dramatically in [bmim][SbF6], allowing the cyanosilylation of a variety of aldehydes and ketones with a turnover frequency up to 48 000 mol h−1 and a total turnover number of 100 000.

We have developed an electrochemically driven strategy for the stereoselective synthesis of protected <i>syn</i>-1,2-diols from vinylarenes with <i>N</i>,<i>N</i>-dimethylformamide (DMF). The newly developed system obviates the need for transition metal catalysts or external oxidizing agents, thus providing an operationally simple and efficient route to an array of protected <i>syn</i>-1,2-diols in a single step. This reaction proceeds <i>via</i> an electrooxidation of olefin, followed by a nucl

Abstract Microwave-assisted Beckmann rearrangements of ketoximes in room temperature ionic liquids have been accomplished successfully using only 5 mol% of H2SO4 as a catalyst.