Green synthesis of 1H‐pyrazolo[1,2‐b]phthalazine‐2‐carbonitrile derivatives using a new bifunctional base–ionic liquid hybrid magnetic nanocatalyst

Abstract

The ionic liquid‐base N,N,2,2,6,6‐hexamethyl‐N‐(3‐(trimethoxysilyl)propyl)piperidin‐4‐amonium iodide was grafted onto titana‐coated NiFe2O4 nanoparticles for obtaining an efficient and reusable ionic liquid‐base hybrid nanocatalyst. The structure of hybrid nanoparticles was characterized using FT‐IR (Fourier‐transform infrared spectroscopy), field emission scanning electron microscopy, EDS (energy‐dispersive X‐ray spectroscopy), EDS map scan, Brunauer–Emmett–Teller surface area analysis, CHN (elemental analysis), vibrating sample magnetometer and thermogravimetric analysis techniques. Furthermore, this novel hybrid catalyst was used in one‐pot three‐component synthesis of 3‐amino‐1‐aryl‐5,10‐dioxo‐1H‐pyrazolo[1,2‐b]phthalazine‐2‐carbonitrile derivatives under green and environmentally benign conditions. This protocol avoids the use of harmful catalysts, toxic solvents and harsh reaction conditions. The products were synthesized in excellent yields within short reaction time and identified using elemental analysis, FT‐IR, 1H NMR and 13C NMR spectroscopies.

A novel magnetic layered double hydroxide as potent mesoporous recyclable heterogeneous nanocatalyst for the synthesis of 1H‐chromeno[2,3‐b]pyridine‐3‐carbonitrile derivatives

“…[13] Among the most popular reported heterogeneous catalysts, supported magnetic nanoparticles (MNPs) have received more attention in the organic synthesis in part due to their excellent catalytic performance, high surface area, improved selectivity, easy product separation, and efficient catalyst recyclability. [14][15][16] However, despite these advantages, MNPs often tend to form large aggregates owing to the strong magnetic dipole-dipole attractions among particles causing them not to disperse well in the reaction mixture. [17] To overcome this drawback, researchers have employed different coatings such as metal-organic framework (MOF), [18] polymers, [19,20] cellulose, [21] chitosan, [22] and layered double hydroxides (LDHs) [23] as protective layers on MNPs in order to improve their catalytic activity in organic reactions [14] and other industrial processes.…”

Synthesis and characterization of a supported Pd complex on volcanic pumice laminates textured by cellulose for facilitating Suzuki–Miyaura cross-coupling reactions

“…In this regard, so many nanoand micro-scaled composites have been designed and introduced for catalytic purposes, in which various types of organic and inorganic materials are used. [13][14][15] Briey, the magnetic materials are commonly used for the convenient separation processes, and the main catalytic active sites are provided by other components such as organic structures, polymers, inorganic particles, biological structures etc. For instance, the surface of the magnetic core has been modied by a polymer, and silver NPs were added and used as the main catalytic site.…”

Fe3O4@nano-almond shell@OSi(CH2)3/DABCO: a novel magnetic nanocatalyst for the synthesis of chromenes

“…11–13 Therefore, derivatization is a prerequisite for any application of nanoparticles, which can be either by activating the surfaces or by stabilizing the functional cores. 14–18…”

“…[11][12][13] Therefore, derivatization is a prerequisite for any application of nanoparticles, which can be either by activating the surfaces or by stabilizing the functional cores. [14][15][16][17][18] 1,4-Diazabicyclo[2.2.2]octane (DABCO), has been widely used in organic synthesis reactions and can serve as a weak base and ligand. DABCO has received considerable attention as a base catalyst for various organic transformations which is easy to handle, inexpensive, eco-friendly, highly reactive, commercially available, shows efficient activity under neat conditions, and is non-toxic.…”