ABSTRACT
A heterogeneous catalyst consisting of bimetallic rhodium-ruthenium particles immobilized on carbon nanotubes was used in the hydroboration reaction and proved highly effective for a variety of alkenes and alkynes. The reactions were carried out with low catalytic loadings (0.04 mol%), under solvent-free conditions, and at room temperature. In addition, to demonstrate its recyclability, the catalyst was recovered by a simple centrifugation process and reused over 5 consecutive cycles without losing any activity.
ABSTRACT
Rhodium nanoparticles were anchored on carbon nanotubes and the resulting nanohybrid was studied as co-catalyst, along with tert-butylcatechol, for the dehydrogenation of various N-heterocycles. The co-catalytic system operates in high yields, under the mildest conditions reported so far, and can be applied to a wide variety of secondary amine-containing scaffolds.
Subject(s)
Catechols/chemistry , Heterocyclic Compounds/chemistry , Metal Nanoparticles/chemistry , Nanotubes, Carbon/chemistry , Rhodium/chemistry , Catalysis , Hydrogen/chemistry , Hydrogenation , Nanotubes, Carbon/ultrastructureABSTRACT
Ruthenium nanoparticles were assembled on carbon nanotubes and the resulting nanohybrid was used in the hydrazine-mediated catalytic hydrogenation of various nitroarenes, at room temperature. Depending on the solvent, a selective transformation occurred, giving either access to the corresponding aniline or hydroxylamine derivative.
Subject(s)
Aniline Compounds/chemistry , Hydroxylamine/chemistry , Nanotubes, Carbon/chemistry , Ruthenium/chemistry , Models, MolecularABSTRACT
A novel nanohybrid structure was synthesized by assembling gold nanoparticles on polymerized polydiacetylene nanotubes. Combination of the nanohybrid with gallacetophenone afforded an efficient cooperative co-catalytic system for the oxidative coupling of primary amines into imines. The system is highly efficient and sustainable as it operates in high yields using minimal amounts of the metal and the quinone, under ambient atmosphere, at room temperature, in water, and is easily recycled.
Subject(s)
Amines/chemistry , Gold/chemistry , Imines/chemistry , Nanotubes/chemistry , Polymers/chemistry , Polyynes/chemistry , Acetophenones/chemistry , Benzoquinones/chemistry , Catalysis , Metal Nanoparticles/chemistry , Oxidative Coupling , Polyacetylene Polymer , Pyrogallol/analogs & derivatives , Pyrogallol/chemistry , Temperature , Water/chemistryABSTRACT
Gold nanoparticles were deposited on carbon nanotubes to provide access to a nanohybrid structure which was involved in the aerobic oxidation of alcohols. The nanohybrid-catalyzed reaction was shown to be highly efficient under mild conditions (i.e. room temperature, air) and selective oxidation of alcohols to the corresponding acids or aldehydes could be achieved, depending on the reaction conditions.
Subject(s)
Alcohols/chemistry , Gold/chemistry , Metal Nanoparticles/chemistry , Nanotubes, Carbon/chemistry , Catalysis , Oxidation-ReductionABSTRACT
New 2,4-thiazolidinediones with aryl sulfonylurea moieties have been synthesized by condensing various substituted sulfonamides and 5-(isocyanatomethyl) thiazolidino-2,4-dione. The isocyanomethyl thiazolidinedione was obtained by using the Curtius rearrangement, starting from known 2,4-dioxo-5-thiazolidineacetic acid. The newly synthesized compounds have been evaluated for the antihyperglycemic activity in normal rats model and among these compounds showed significant antihyperglycemic activity in sucrose loaded rat model.
Subject(s)
Diabetes Mellitus/drug therapy , Hypoglycemic Agents/pharmacology , Sulfonylurea Compounds/chemistry , Thiazolidinediones/chemical synthesis , Thiazolidinediones/pharmacology , Animals , Blood Glucose/drug effects , Chemistry, Pharmaceutical/methods , Chromatography, Thin Layer/methods , Drug Design , Male , Models, Chemical , Rats , Rats, Sprague-Dawley , Sucrose/chemistry , Time FactorsABSTRACT
A convenient and scalable four-step novel route has been developed for the synthesis of rosiglitazone (8), an antidiabetic drug. This multistep route requires 4-fluoro benzaldehyde (4), 2,4-thiazolidinedione (6) and 2-chloro pyridine (1) as key reactants and gives overall better yield of rosiglitazone. In addition, some steps have been accelerated, which leads to an overall time saving of 10h.
