17975-50-7Relevant articles and documents
N-bromosuccinimide (NBS)-promoted, three-component synthesis of α,β-unsaturated isoxazol-5(4H)-ones, and spectroscopic investigation and computational study of 3-methyl-4-(thiophen-2-ylmethylene)isoxazol-5(4H)-one
Kiyani, Hamzeh,Kanaani, Ayub,Ajloo, Davood,Ghorbani, Fatemeh,Vakili, Mohammad
, p. 7739 - 7773 (2015)
A three-component, NBS-promoted synthesis of α,β-unsaturated isoxazol-5(4H)-ones by reaction of aromatic aryl or hetero-aryl aldehydes, hydroxylamine hydrochloride, and 1,3-dicarbonyl compounds (ethyl acetoacetate or ethyl 4-chloroacetoacetate), under mild reaction conditions at room temperature is described. This simple, efficient, and clean reaction is an expeditious means of obtaining the corresponding isoxazol-5(4H)-one derivatives in good to high yields. Geometrical properties and vibrational wavenumbers of 3-methyl-4-(thiophen-2-ylmethylene)isoxazol-5(4H)-one (MTISO) were predicted by use of density functional theory (DFT) by use of the B3LYP level with the 6-311++G(d,p) and 6-311++G(2d,p) basis sets. Results indicate that the B3LYP method enables satisfactory prediction of vibrational frequencies and structural data. The absorption spectra of MTISO in solvents of different polarity were studied at room temperature. The UV-visible spectrum of the compound was recorded and such electronic properties as the energies of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) were determined by the time-dependent DFT (TD-DFT) approach. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization was studied by NBO analysis. A molecular electrostatic potential map (MEP) of the compound was also studied to predict reactive sites. Reactivity descriptors, Fukui functions, and electrophilic sites were found and are discussed. The thermal stability of MTISO was studied by thermogravimetric analysis (TGA).
An efficient solvent-free synthesis of 3,4-disubstituted isoxazole-5(4H)-ones using microwave irradiation
Kulkarni, Pramod
, (2021/06/28)
I have reported one-pot and three-component synthesis of 3-mehyl-4-arylmethyleneisoxazol-5(4H)-ones using microwave radiation under the solvent-free conditions, in the presence of potassium bromide as the catalyst. The method has given the products in hig
Facile and expedient synthesis of α,β-unsaturated isoxazol-5(4H)-ones under mild conditions
Ghorbani, Fatemeh,Kiyani, Hamzeh,Pourmousavi, Seied Ali
, p. 943 - 959 (2019/11/13)
Abstract: It was found that nano-SiO2–H2SO4 was catalyzed by the three-component cyclocondensation of aryl/heteroaryl aldehydes, hydroxylamine hydrochloride, and β-ketoesters toward the synthesis of α,β-unsaturated?isoxazol-5(4H)-ones under green conditions. The reaction yielded the corresponding heterocycles at room temperature in relatively shorter reaction times. It merits mentioning that the mild conditions allow the synthesis of several α,β-unsaturated?isoxazol-5(4H)-ones using this method. In this study, some new derivatives of isoxazolones were also synthesized and characterized. It is efficient, clean, simple, safe, and ecologically friendly. This straightforward method is cost-effective and requires no preparation of reactants. The three-component annulation was performed without using energy sources, for example, heat, ultrasound wave, and microwave irradiation. Graphic abstract: [Figure not available: see fulltext.].
