A new silver coordination polymer based on 4,6-diamino-2-pyrimidinethiol: synthesis, characterization and catalytic application in asymmetric Hantzsch synthesis of polyhydroquinolines

Abstract

A highly efficient and stable heterogeneous coordination polymer (CP) was successfully prepared by hydrothermal combination of silver and 4,6-diamino-2-pyrimidinethiol. The prepared coordination polymer was characterized by FT-IR, XRD, TGA, SEM, EDX, X-ray mapping and Nitrogen adsorption–desorption analysis. The prepared Ag–CP exhibit excellent catalytic activity in multicomponent Hantzsch synthesis of polyhydroquinolines under mild reaction conditions in relatively short reaction times. The heterogeneity of the catalyst was confirmed by the hot filtration test; also, the catalyst was reused for at least four times under the optimized reaction conditions without any significant loss of its catalytic activity.

Ni–citric acid coordination polymer as a practical catalyst for multicomponent reactions

“…8 ). In the TGA curve, the two obvious weight losses were found in the temperature range of 50–270 °C, which can be attributed to the release of the physically adsorbed moisture (water) and DMF solvents from the sample 15 . In this sense, it was at above 270 °C that the framework degradation started.…”

“…3 c). In addition, the peaks at the region of 2855–2928 cm −1 can be regarded as the characteristic of the stretching vibrations of aliphatic C–H 15 . The presence of aliphatic C–H stretching vibration indicates that the organic ligand used in the final sorbent structure remained and was not destroyed.…”

“…In this regard various heterogeneous and homogeneous (Transition metals, transition metal complexes or supported metals) catalysts are employed in MCRs to increase selectivity and rate of the reaction 4 , 14 . For example, multicomponent reactions have been significantly extended using Coordinative polymers (CP) 15 . Coordinative polymers are commonly formed by transition metal ions and an organic multi-dentate ligand 15 , 16 .…”

“…For example, multicomponent reactions have been significantly extended using Coordinative polymers (CP) 15 . Coordinative polymers are commonly formed by transition metal ions and an organic multi-dentate ligand 15 , 16 . CP platforms with unique properties such as easy recoverability, large pore aperture, low density, high specific surface area, permanent nanoscale porosity and uniform structured cavities, have been used as ideal catalysts in MCRs and other applications such as drug delivery, gas storage, separation science, gas purification, sensing, optoelectronics, magnetism and luminescence 17 – 22 .…”

Bimetallic Fe–Cu metal organic frameworks for room temperature catalysis

“…Recently, there has been attracted outstanding attention to use of heterogeneous catalysts with extraordinary activity, high surface area to volume, and good recyclability in different organic reactions such as remove or conversion of pollutants, for example, nitro groups and organic dyes. [29][30][31][32][33][34][35] Metal-organic frameworks (MOFs) are new crystalline porous compounds prepared from metallic ions and organic linkers that cause the formation of one-, two-and three-dimensional solids. [36][37][38] MOFs have currently attracted extensive attention due to their unique features containing high special surface area, high porosity, [39] structural variability, [40] and excellent thermal stability.…”