Search results for "4-OXADIAZOLE"
showing 10 items of 65 documents
Fluorinated Heterocyclic Compounds. A Photochemical Approach to a Synthesis of Polyfluoroaryl-1,2,4-triazoles.
2005
The reaction of some fluorinated 1,2,4-oxadiazoles in the presence of methylamine or propylamine has been investigated. The irradiation in methanol or acetonitrile leads with acceptable yields to the corresponding fluorinated 1- methyl- or 1-propyl-1,2,4-triazole.
Synthesis and characterization of a series of alkyl-oxadiazolylpyridinium salts as perspective ionic liquids
2007
The synthesis of a series of 1,2,4-oxadiazolyl-N-methylpyridinium salts differing in the length and the position of the alkyl chain in the heterocyclic ring and the counter ions is reported. Some features of this new family of salts as perspective ionic liquids are described and the influence of the varying moieties in the modulation of the properties is discussed.
On the photoreaction of some 1,2,4-oxadiazoles in the presence of2,3-dimethyl-2-butene. Synthesis of N-imidoyl-aziridines
2007
Fhe photochemistry of some 3,5-disubstituted 1,2,4-oxadiazoles in the presence of 2,3-dimethyl-2-butene has been investigated. The irradiation in acetonitrile yielded differently substituted N-imidoyl-aziridines through an aziridination reaction involving an acyliminonitrene intermediate. Pyrolysis of N-imidoyl-aziridines produced the corresponding N-allylamidines through a ring opening process.
Synthesis of fluorinated first generation starburst molecules containing a triethanolamine core and 1,2,4-oxadiazoles
2006
Abstract 5-Pentafluorophenyl-1,2,4-oxadiazoles, differently substituted at C(3), have been synthesized and used to functionalize the aliphatic primary hydroxyl functionalities of triethanolamine, under mild conditions. UV–visible absorption and emission spectra are reported, for both tri- and difunctionalised molecules, showing their potential applications as light-emitters in optoelectronic devices.
Photochemistry of Fluorinated Heterocyclic Compounds. An Expedient Route for the Synthesis of Fluorinated 1,3,4-Oxadiazoles and 1,2,4-Triazoles
2004
The photochemistry of some 3-N-alkylamino-5-perfluoroalkyl-1,2,4-oxadiazoles in the presence of nitrogen nucleophiles such as ammonia and primary and secondary aliphatic amines has been investigated. The primary photolytic intermediate from the cleavage of the ring O-N bond follows two distinct and competing pathways leading to (i). 5-perfluoroalkyl-1,3,4-oxadiazoles, through the ring contraction-ring expansion photoisomerization route favored by the presence of the base or (ii). 5-perfluoroalkyl-1,2,4-triazoles, through the intervention, as an internal nucleophile, of the exocyclic N-alkylamino moiety of the oxadiazole followed by the attack of the external nitrogen nucleophile and subsequ…
Ru(bpy)2Cl2: A catalyst able to shift the course of the photorearrangement in the Boulton-Katritzky reaction
2015
The Boulton-Katritzky reaction represents one of the most popular and efficient strategies used to realize azole-into-azole conversions. For example, under different experimental conditions, it allows the rearrangement of Z-arylhydrazones of 3-benzoyl-5-phenyl-1,2,4-oxadiazoles (1) into 2-aryl-4-benzoylamino-5-phenyl-2H-1,2,3-triazoles (2) in very high yields. Moreover, we have recently realized this conversion also by UV-photostimulation. Now we have enlarged the scope of the reaction irradiating with visible or UV light an acetonitrile solution of some Z-arylhydrazones (1a-e) in the presence of catalytic amounts of Ru(bpY)(2)Cl-2. We have observed the unexpected formation of the 1-aryl-5-…
Synthesis and chemical characterization of CuII, NiII and ZnII complexes of 3,5-bis(20-pyridyl)-1,2,4-oxadiazole and 3-(20-pyridyl)5-(phenyl)-1,2,4-o…
2011
The synthesis and structural characterization of NiII, CuII and ZnII complexes of two chelating 1,2, 4-oxadiazole ligands, namely 3,5-bis(20-pyridyl)-1,2,4-oxadiazole (bipyOXA) and 3-(20-pyridyl)5- (phenyl)-1,2,4-oxadiazole (pyOXA), is here reported. The formed hexacoordinated metal complexes are [M(bipyOXA)2(H2O)2](ClO4)2 and [M(pyOXA)2(ClO4)2], respectively (M = Ni, Cu, Zn). X-ray crystallography, 1H and 13C NMR spectroscopy and C, N, H elemental analysis data concord in attributing them an octahedral coordination geometry. The two coordinated pyOXA ligands assume a trans coplanar disposition, while the two bipyOXA ligands are not. The latter result is a possible consequence of the format…
Synthesis and biological evaluation of new 1,2,4-oxadiazole derivatives of Topsentin
Solvent dependent photochemical reactivity of 3-allyloxy-1,2,4-oxadiazoles
2009
CCDC 915396: Experimental Crystal Structure Determination
2013
Related Article: M.Saccone,G.Cavallo,P.Metrangolo,A.Pace,I.Pibiri,T.Pilati,G.Resnati,G.Terraneo|2013|CrystEngComm|15|3102|doi:10.1039/C3CE40268A