A joint experimental and theoretical structural study of novel substituted 2,5-dioxo-1,2,3,4,5,6,7,8-octahydroquinolines
摘要:
A series of substituted 2,5-dioxo-1,2,3,4,5,5,7,8-octahydroquinolines have been synthesised from Meldrum's acid and dimedone in the presence of different aldehydes by following an approach similar to the one developed by Hantzch. The structure of these compounds has been thoroughly studied by X-ray crystallographic analysis and semiempirical (AM1) and ab initio (HF/3-21G) methods, and two favoured conformations are possible. A good agreement is found between the theoretical and experimental values. The most stable conformation (A) in the solid state is also that favoured in solution, according to the proton coupling constant determined from Karplus' and Altona's equations and H-1 NMR spectroscopic experiments. (C) 1998 Elsevier Science Ltd. All rights reserved.
A simple, efficient, and environmentally benign protocol for the synthesis of polyhydroquinoline derivatives was developed using a bio-compatible, heterogeneous, and recoverable mesoporous ionic liquid supported nanoporous silica as a nano-catalyst. The polyhydroquinoline derivatives were obtained by the four-component reaction of aldehyde, Meldrum’s acid, dimedone, and ammonium acetate in excellent yields .
One-Pot Synthesis of 1,4-Dihydropyridine Derivatives Catalyzed by Silica-Coated Magnetic NiFe2O4 Nanoparticles-Supported H14[NaP5W30O110]
作者:B. Maleki、A. V. Mofrad、R. Tayebee、A. Khojastehnezhad、H. Alinezhad、E. Rezaei Seresht
DOI:10.1134/s1070363217120325
日期:2017.12
Silica-coated magnetic NiFe2O4 nanoparticles-supported H-14[NaP5W30O110] (NiFe2O4@SiO2-H-14[NaP5W30O110]) was successfully synthesized and shown to be a versatile and highly efficient heterogeneous catalyst for one-pot multicomponent synthesis of 1,4-dihydropyridine derivatives under solvent-free condition. The synthesized catalyst can be magnetically recovered and reused four times without significant loss in catalytic efficiency.