ABSTRACT
A general and efficient Cu(I)-mediated cross-coupling and heterocyclization reaction of 3-iodoimidazo[1,2-a]pyridine-2-carboxylic acid, and terminal alkynes was developed under very mild conditions. This method allows the introduction in one pot of a third ring fused in positions 2 and 3 of the imidazo[1,2-a]pyridine core with reasonable yields and total regioselectivity. This procedure does not require the use of any expensive supplementary additives, and is palladium-free.
Subject(s)
Copper/chemistry , Imidazoles/chemistry , Pyridones/chemistry , Catalysis , Cyclization , Molecular Structure , Palladium/chemistryABSTRACT
Three-component reactions with 3,4-diiodoalk-2-enoic derivatives, primary amines, and terminal alkynes proceeded to give trisubstituted pyrroles in fair to good yields in the presence of palladium and copper catalysts under mild reaction conditions.
Subject(s)
Palladium/chemistry , Pyrroles/chemical synthesis , Alkynes/chemistry , Amines/chemistry , Catalysis , Copper/chemistry , Cyclization , Pyrroles/chemistryABSTRACT
The present study reports on the formation of supramolecular fibers from a novel cyclen-based ligand and metal salts. In particular, the fibers were shown to stabilize supramolecular porous materials of low density. It was also demonstrated that these fibers could be functionalized by radical polymer growth on their surface. Such new supramolecular fibers constitute a simple and tunable starting material for the synthesis of 1D core-shell objects.
Subject(s)
Nanofibers/chemistry , Cyclams , Heterocyclic Compounds/chemistry , Ligands , Metals/chemistry , Methacrylates/chemistry , Nanofibers/ultrastructure , PorosityABSTRACT
A general route to alpha-pyrones and 3-substituted isocoumarins from (Z)-iodovinylic acids 1a-f or 2-iodobenzoic acids 4a-c is described, including compounds bearing a substituent on the aromatic ring. Treatment of (Z)-beta-iodovinylic acids 1a-f or 2-iodobenzoic acids 4a-c with various allenyltributyltin reagents in the presence of palladium acetate, triphenylphosphine, and tetrabutylammonium bromide in dimethylformamide provided good yields of the corresponding alpha-pyrones 3a-k or 3-substituted isocoumarins 5a-g via tandem Stille reaction and 6-endo-dig oxacyclization.
Subject(s)
Isocoumarins/chemical synthesis , Pyrones/chemical synthesis , Cyclization , Magnetic Resonance Spectroscopy , Spectrometry, Mass, Electrospray IonizationABSTRACT
(Z)-Ethyl-3-perfluoroalkyl-3-magnesiated crotonates were prepared from (Z)-ethyl-3-perfluoroalkyl-3-iodo enoates by iodine-magnesium exchange reaction with isopropylmagnesium bromide in THF at -78 degrees C. These new reagents reacted with a range of electrophiles, leading to polyfunctional products bearing a perfluoroalkyl group.
ABSTRACT
Electron impact mass spectra of iodinated tropane derivatives which are of clinical importance are described. The major fragment ions were found to come from the cleavage of the Calpha-Cbeta bond of the bridgehead nitrogen, affording to hydrogenopyrrolidine derivatives ions. The fragment ions generated from the EI mass spectra were assigned and fragmentation mechanisms were proposed.
Subject(s)
Cocaine/analogs & derivatives , Cocaine/chemical synthesis , Dopamine/chemistry , Membrane Glycoproteins/chemistry , Membrane Transport Proteins/chemistry , Nerve Tissue Proteins/chemistry , Chromatography, High Pressure Liquid , Cocaine/chemistry , Dopamine Plasma Membrane Transport Proteins , Gas Chromatography-Mass Spectrometry , Ligands , Molecular StructureABSTRACT
Palladium-catalyzed stereoselective annulation of a functional vinylstannane by acyl chlorides gives the corresponding alpha-pyran-2-ones in good yields. This annulation most probably proceeds through a Stille reaction/cyclization sequence.