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The paper describes our studies on ion pair interactions in ionic liquids (IL) using an asymmetric hydrogenation reaction as probe. Three different ionic liquids carrying prochiral keto-functionalized cations were hydrogenated in the presence of their chiral, enantiomerically pure counter-ion using an achiral heterogeneous ruthenium catalyst. For the hydrogenation of N-(3′-oxobutyl) -N-methylimidazolium camphorsulfonate (2), N-(3′-oxobutyl)imidazolium camphorsulfonate (4) and N-(5′-oxohexyl)-N-methylimidazolium camphorsulfonate (6) we found a strong dependency of the enantiomeric excess (ee in the cation) on the polarity of the solvent, the concentration of the IL and the structure of the IL. The highest ee values of up to 94% were found for the hydrogenation of 2 in ethanol. Interestingly, we observed that the ee (and consequently the strength of ion pair interaction) had a pronounced maximum for a certain concentration of the IL in the solvent depending on the nature of the solvent and on the substrate. Remarkably, the concentration leading to the maximum ee could be rationalized by independent determination of the degree of dissociation which was obtained by a combination of diffusion-ordered NMR spectroscopy and conductivity measurements.

Provided herein are compounds having activity against TTR related conditions, and pharmaceutically accepted salts and solvates thereof. Also provided are methods of using the compounds for inhibiting and preventing TTR aggregation and/or amyloid formation in the peripheral nerves, kidney, cardiac tissue, eye and CNS, and of treating a subject with peripheral TTR amyloidosis.

TiCl2(OTf)-SiO2 is simply prepared by immobilization of TiCl3(OTf) on silica gel surface and introduced as a non-hygroscopic Lewis acid catalyst for C-N and C-C bond formation via Michael addition reaction. A variety of structurally diverse nitrogen nucleophiles including α-aminophosphonates, aliphatic and aromatic amines and imidazole were evaluated as Michael donors. Friedel–Crafts alkylation of indoles and pyrrole was also investigated through Michael addition reaction in the presence of TiCl2(OTf)-SiO2 as a catalyst. The reactions were conducted at room temperature or 60 °C under solvent-free conditions and the desired Michael adducts were obtained in high to excellent yields.

Metal N-heterocyclic carbene (NHC) complexes are a promising class of anti-cancer agents displaying potent in vitro and in vivo activities. Taking a multi-faceted approach employing two clickable photoaffinity probes, herein we report the identification of multiple molecular targets for anti-cancer active pincer gold(III) NHC complexes. These complexes display potent and selective cytotoxicity against cultured cancer cells and in vivo anti-tumor activities in mice bearing xenografts of human cervical and lung cancers. Our experiments revealed the specific engagement of the gold(III) complexes with multiple cellular targets, including HSP60, vimentin, nucleophosmin, and YB-1, accompanied by expected downstream mechanisms of action. Additionally, PtII and PdII analogues can also bind the cellular proteins targeted by the gold(III) complexes, uncovering a distinct pincer cyclometalated metal–NHC scaffold in the design of anti-cancer metal medicines with multiple molecular targets.

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Ionic liquid (IL) tagged organocatalysts based on TADDOL (α, α, α′, α′-tetraaryl-2,2-dimethyl-1,3-dioxolane-4,5- dimethanol) comprising various aryl substituents tethered with triazolium and imidazolium based ionic liquids are synthesised in good yields.

A series of aryloxy alkyl/aryl alkyl imidazoles were synthesized and evaluated in vitro as antileishmanials against Leishmania donovani. All the 19 compounds exhibited 94-100% inhibition at 10 μg/mL against promastigotes and 12 compounds exhibited high in

An efficient aza-Michael addition of amines to a variety of activated olefins was carried out under solvent free conditions using iodine-alumina as a catalyst at room temperature or under microwave irradiation (in case of solid) in high yield. 2009 Bentham Science Publishers Ltd.

Aliphatic and aromatic amines undergo smooth nucleophilic addition to α,β-unsaturated compounds in the presence of a catalytic amount of silica-supported aluminum chloride at 60°C and under solvent-free conditions to produce the corresponding β-amino compounds in excellent yields. This method is simple and convenient and works efficiently under mild conditions. This catalyst can used again without losing its activity three times. Copyright Taylor & Francis Group, LLC.

N-Methylimidazole has been shown to be a promising catalyst for aza-Michael reactions. Various N-heterocycles were introduced to α,β-unsaturated carbonyl compounds employing N-methylimidazole (0.05 equiv) in a highly efficient, rapid and high yielding syn

(Chemical Equation Presented). Conjugate addition of heteroatom nucleophiles to carbon-carbon double bonds conjugated with a strong electron-withdrawing group is one of the most important new bond-forming strategies in synthetic organic chemistry. Among the methods for these Michael additions, Lewis acids have shown the best promoter activity, and in particular, the use of reagents impregnated over inorganic supports is rapidly increased. With the increase of environmental consciousness in chemical research, the solvent-free Michael addition has attracted our attention. In continuation of our ongoing program to develop synthetic protocols utilizing cerium trichloride, we report an extension of the CeCl3·7H2O/NaI combination supported under solvent-free conditions to promote heteroatom Michael addition. Using neutral alumina (Al2O3) as solid support permits us to circumvent some of the problems associated with the procedure where the inorganic support is silica gel. The CeCl 3· 7H2O/NaI/Al2O3 system works well for hetero-Michael additions utilizing weakly nucleophiles such as imidazoles and carbamates, and also the reaction proceeds with good yields in the case of Michael acceptors different from α,β-unsaturated carbonyl compounds. An important synthetic application of this our methodology is the intramolecular aza-Michael reaction in producing 4-piperidinone derivatives, which are of interest as synthetic intermediates toward important classes of heterocycles.

Sodium dodecyl sulfate (SDS) catalyzes facile Michael additions of amines and thiols to α,β-unsaturated ketones under neutral micellar conditions to afford the corresponding Michael adducts in good to high yields.

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