Poly(4-vinyl pyridine) supported nanoparticle of copper(Ⅰ) iodide is reported as a green and recyclable catalyst for the regioselective synthesis of 1,4-disubstituted-1H-1,2,3-triazoles from benzyl halides,sodium...Poly(4-vinyl pyridine) supported nanoparticle of copper(Ⅰ) iodide is reported as a green and recyclable catalyst for the regioselective synthesis of 1,4-disubstituted-1H-1,2,3-triazoles from benzyl halides,sodium azide and terminal alkynes in water. This catalyst can be recovered by simple filtration and recycled up to 8 consecutive runs without any loss of its efficiency.展开更多
A new catalytic procedure for the chemoselective oxidation of sulfides to sulfoxides was studied.A variety of aliphatic and aromatic sulfides were subjected to sulfoxidation by combining poly(4-vinyl pyridinium nitrat...A new catalytic procedure for the chemoselective oxidation of sulfides to sulfoxides was studied.A variety of aliphatic and aromatic sulfides were subjected to sulfoxidation by combining poly(4-vinyl pyridinium nitrate),silica sulfuric acid(SiO2-OSO3H),and catalytic amounts of ammonium bromide in CH2Cl2 in the presence of a few drops of water at room temperature.Excellent yields were obtained.展开更多
Poly(4\|vinyl phenol) (PVPh) was synthesized from anisaldehyde via Perkin Doebner and decarboxyl reactions to form 4 methoxy styrene.It was then polymerized by free radical polymerization following dealkylation to for...Poly(4\|vinyl phenol) (PVPh) was synthesized from anisaldehyde via Perkin Doebner and decarboxyl reactions to form 4 methoxy styrene.It was then polymerized by free radical polymerization following dealkylation to form PVPh.A kind of stable multilayer utra thin film was successfully fabricated via self assembly technique from PVPh and diazoresin (DR) followed by UV irradiation.The driving force of self assembly was confirmed to be the hydrogen bonding attraction from diazonium group(—N + 2)of DR and phenolic hydroxy group(—Ph—OH)of PVPh.The film becomes very stable towards polar solvents after UV irradiation and it is believed that the H bonds between the layers of the film converts to covalent bonds following the decomposition of —N + 2 groups when the multilayer film underwent UV irradiation.展开更多
The effect of UV irradiation and blending with phthalate and terephthalate plasticizers on the photo-stability of Poly (4-vinyl biphenyl) was studied at different intervals of irradiation time and in presence of air. ...The effect of UV irradiation and blending with phthalate and terephthalate plasticizers on the photo-stability of Poly (4-vinyl biphenyl) was studied at different intervals of irradiation time and in presence of air. The increase in irradiation time on the photodegradation of polymer thin films caused a change in the intensity and shape of the fluorescence band. It has been found that the stability of the polymer decreases with the increase of irradiation time, and to increases with the increase of the amount of added phthalate and terephthalate plasticizers, which is evidence of polymer photodegradation. The FT-IR spectra of irradiated pure and blended polymer with phthalate and terephthalate plasticizers showed a decrease in some absorption bands and increase in the other bands, this is also another factor for the occurrence of photo degradation of the irradiated polymer. The increase in the intensity of absorption of carbonyl and hydroxyl region, indicates a possible photogegradation of polymeric chains and the formation of alcohols, aliphatic ketones and to the increase in the number of (C=C) that resulted from hydrogen abstraction during chains-scission.展开更多
文摘Poly(4-vinyl pyridine) supported nanoparticle of copper(Ⅰ) iodide is reported as a green and recyclable catalyst for the regioselective synthesis of 1,4-disubstituted-1H-1,2,3-triazoles from benzyl halides,sodium azide and terminal alkynes in water. This catalyst can be recovered by simple filtration and recycled up to 8 consecutive runs without any loss of its efficiency.
基金Supported by the research facilities of Ilam University,Ilam,Iran
文摘A new catalytic procedure for the chemoselective oxidation of sulfides to sulfoxides was studied.A variety of aliphatic and aromatic sulfides were subjected to sulfoxidation by combining poly(4-vinyl pyridinium nitrate),silica sulfuric acid(SiO2-OSO3H),and catalytic amounts of ammonium bromide in CH2Cl2 in the presence of a few drops of water at room temperature.Excellent yields were obtained.
文摘Poly(4\|vinyl phenol) (PVPh) was synthesized from anisaldehyde via Perkin Doebner and decarboxyl reactions to form 4 methoxy styrene.It was then polymerized by free radical polymerization following dealkylation to form PVPh.A kind of stable multilayer utra thin film was successfully fabricated via self assembly technique from PVPh and diazoresin (DR) followed by UV irradiation.The driving force of self assembly was confirmed to be the hydrogen bonding attraction from diazonium group(—N + 2)of DR and phenolic hydroxy group(—Ph—OH)of PVPh.The film becomes very stable towards polar solvents after UV irradiation and it is believed that the H bonds between the layers of the film converts to covalent bonds following the decomposition of —N + 2 groups when the multilayer film underwent UV irradiation.
文摘The effect of UV irradiation and blending with phthalate and terephthalate plasticizers on the photo-stability of Poly (4-vinyl biphenyl) was studied at different intervals of irradiation time and in presence of air. The increase in irradiation time on the photodegradation of polymer thin films caused a change in the intensity and shape of the fluorescence band. It has been found that the stability of the polymer decreases with the increase of irradiation time, and to increases with the increase of the amount of added phthalate and terephthalate plasticizers, which is evidence of polymer photodegradation. The FT-IR spectra of irradiated pure and blended polymer with phthalate and terephthalate plasticizers showed a decrease in some absorption bands and increase in the other bands, this is also another factor for the occurrence of photo degradation of the irradiated polymer. The increase in the intensity of absorption of carbonyl and hydroxyl region, indicates a possible photogegradation of polymeric chains and the formation of alcohols, aliphatic ketones and to the increase in the number of (C=C) that resulted from hydrogen abstraction during chains-scission.