نتایج جستجو برای: hantzsch reaction
تعداد نتایج: 412554 فیلتر نتایج به سال:
This work concerns the synthesis of poly(pyrazolopyridine)s via a three-component Hantzsch reaction. The first part this study was intended to determine adequate experimental conditions for an analytically pure pyrazolopyridine heterocycle model compound in quantitative yield, which can be further used polymer synthesis. For purpose, effect different parameters (solvent, temperature, additive) ...
We describe an assay for ethylene glycol in serum, which is based on the Hantzsch condensation reaction. Ethylene glycol is dehydrogenated by sodium periodate to form two molecules of formaldehyde, which is then combined with ammonium ion and acetylacetone to form a fluorescent diacetyllutidine derivative. The detection limit of this method is 50 mg/L. The procedure is sensitive, requires only ...
New aryl-hydrazinyl-1,3-selenazole and aroyl-hydrazonyl-1,3-selenazoles were synthesized via Hantzsch type condensation reactions of selenosemicarbazides with α-halogenocarbonyl derivatives, under classical versus microwave heating conditions. Excellent yields and shorter reaction times were obtained under irradiation conditions. The structures of the synthesized compounds were assigned based o...
An efficient enantioselective synthesis of the chiral polycyclic cholesteryl ester transfer protein (CETP) inhibitor 1 has been developed. The synthesis was rendered practical for large scale via the development of a modified Hantzsch-type reaction to prepare the sterically hindered pyridine ring, enantioselective hydrogenation of hindered ketone 6 utilizing novel BIBOP-amino-pyridine derived R...
Silica boron sulfonic acid [SiO2–B(OSO3H)3] as an inexpensive, reusable, and Lewis and Brønsted acid catalyst was successfully synthesized, and used for the one-pot three-components synthesis of biologically active substituted Hantzsch 1,4-dihydropyridine derivatives in the absence of solvent at 90ºC. Silica boron sulfonic acid is attractive and efficient, because it plays in two role as a Lew...
The use of domino and multicomponent reactions in asymmetric synthesis is constantly increasing nowadays. This allows for the synthesis of complex molecules in a single synthetic sequence, usually with high atom economy. Herein, we report three examples of new asymmetric tandem reactions recently developed in our laboratories, giving rise to new families of enantiomerically enriched fluorinated...
In this study, multi component Hantzsch reaction was carried out between various Aromatic Aldehyde with Dimedone,Ethyl acetateand ammonium acetate to produce polyhydroquinolinederivatives under solvent-free conditions at 110oC by a (Zinc oxide nanocatalyst) as effective Lewis acid. The remarkable advantages offered by this method compared with other methods are a green catalyst, si...
a simple and mild one-pot three-component reaction for the preparation 1,4-dihydropyridines has been developed from various aldehyde substrates, 1,3-dicarbonyl compounds (dimedone) and ammonium acetate (hantzsch method) in the presence of a catalytic amount of phospho sulfonic acid (psa) as an efficient and heterogeneous solid acid in etoh at room temperature. preparation of psa is straightforw...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید