نتایج جستجو برای: 4h chromenes

تعداد نتایج: 6923  

The synthesis of pharmaceutically and biologically active 2-amino-4H-chromenes was described using TiO2/nanoclinoptilolite (TiO2/NCP) as an efficient nanocatalyst under solvent-free condition. The TiO2/NCP was fabricated through modification of NCP with HDTMA, then the surface modified NCP was impregnated with titanium tetrachloride solution. Finally, the materi...

Journal: :iranian journal of catalysis 2015
leila moradi mina zare

a simple, mild and high efficient procedure for one pot three component synthesis of 2-amino 4-h chromene derivatives was studied. the reaction was performed in water using aryl aldehydes, malononitrile and resorcinol, phloroglucinol or naphthole in the presence of n-methyl d-glucamine (meglumine) as a green high efficient catalyst. the reaction was studied in thermal, microwave (mw) and ultras...

Journal: :Chemical science 2014
Bi-Shun Zeng Xinyi Yu Paul W Siu Karl A Scheidt

An enantioselective Pd-catalyzed 6-endo-trig reaction for the synthesis of 2-aryl-chromenes has been developed. A systematic optimization of a TADDOL-derived ligand set resulted in the identification of a novel monodentate phosphoramidite-palladium catalyst that accesses 2-aryl-2H-chromenes with high yield and enantioselectivity under mild conditions. The products obtained from this method can ...

1997
G. P. Kalena

A convenient one-step synthesis of 2,2-dimethylchromans and chromenes using Amberlyst 15 as a catalyst is described.

Some chromeno[4′,3′-b]pyrano[6,5-b]quinoline derivatives were synthesized by condensation of 2-amino-4-aryl-3-cyano-5-oxo-4H, 5H -pyrano-[3,2-c] chromenes and 1,3-cyclohexanedione in an environmentally benign and efficient method by Cu(II)-Schiff base/SBA-15 as an environmentally friendly heterogeneous and recyclable catalyst under solvent-free conditions in high yields and rates. These kinds o...

The synthesis of pharmaceutically and biologically active 2-amino-4H-chromenes was described using TiO2/nanoclinoptilolite (TiO2/NCP) as an efficient nanocatalyst under solvent-free condition. The TiO2/NCP was fabricated through modification of NCP with HDTMA, then the surface modified NCP was impregnated with titanium tetrachloride solution. Finally, the materi...

Journal: :Organic & biomolecular chemistry 2015
Jun-Hua Li Da-Ming Du

An efficient protocol for the asymmetric construction of enantiomerically enriched tetrahydro-6H-benzo[c]chromenes and their derivatives has been developed. The corresponding products were obtained by the cascade double Michael addition of 3-nitro-2H-chromenes and their derivatives with α,β-unsaturated ketones catalyzed by a combination of a quinine-derived primary amine and benzoic acid. Throu...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید