Synthetic strategies of pyran derivatives by multicomponent reaction (MCR) approach

Nawaz, Anam; Aslam, Sana; Ahmad, Matloob; Zahoor, Ameer Fawad; Naqvi, Syed Ali Raza

doi:10.1007/s13738-022-02581-0

“…The importance of MCRs in chemistry is because of their simplicity, selectivity, high productivity, reduced number of synthesis steps and so reaction time, low energy consumption, and waste production. [30,31] Among the heterocyclic compounds, 4H-pyran and its derivatives including six-membered ring heterocycles with oxygen have attracted considerable attention due to their diverse properties. [32] Following our previous efforts for the development of green catalytic protocols for various synthetic transformations [17] and regarding the principles of green chemistry, in this research, we synthesized of a copper (II) Schiff base complex supported on magnetic GO (GO/Fe 3 O 4 /CuL) as an efficient, heterogeneous, and recyclable nanocatalyst for the onepot synthesis of 2-amino-4H-benzo[h]chromene derivatives in the presence of malononitrile and 1-naphthol with different aldehydes.…”

Section: Introductionmentioning

confidence: 99%

Copper Schiff base complex immobilized on magnetic graphene oxide: Efficient heterogeneous nanocatalyst for treating environmental pollutants and synthesis of chromenes

Dastjerd

¹

,

Monadi

²

2022

Applied Organom Chemis

4

0

View full text Add to dashboard Cite

Herein, a new Cu(II) Schiff base complex was immobilized onto the magnetic graphene oxide surface through a stepwise procedure. The as‐synthesized nanostructure (GO/Fe3O4/CuL) was characterized by various techniques including Fourier transform infrared (FT‐IR), Raman spectroscopies, scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), energy‐dispersive X‐ray (EDX) and inductively coupled plasma (ICP) spectroscopies, N2 adsorption–desorption analysis, vibrating sample magnetometry (VSM), and X‐ray diffraction (XRD). The catalytic activity of the synthesized nanocatalyst was examined in 4‐nitrophenol (4‐NP), Congo red (CR), and methylene blue (MB) reduction using NaBH4 in an aqueous solution at room temperature. The reaction progress was monitored by UV–Vis spectroscopy. Also, the synthesized nanostructure was evaluated as an efficient catalyst for the synthesis of 2‐amino‐4H‐benzopyrans via three‐component reactions of 1‐naphthol, malononitrile, and various aldehydes in ethanol/water at 50°C. The use of green solvents, the short reaction time, the high product yield, and easy separation from the reaction environment are the main benefits of this catalytic system. By covalent grafting of the complex on the graphene oxide surface, its catalytic performance significantly increased compared with graphene oxide; this is probably related to the chemical change of the graphene oxide surface. The results show the high chemical stability and the improved reusability of the synthesized nanocatalyst (six times) without significant loss in the catalytic activity of GO/Fe3O4/CuL nanocomposite.

show abstract

A Hollowed‐Out Heterometallic Cluster for Catalytic Knoevenagel Condensation

Chen,

Xu,

Qin

et al. 2024

Angewandte Chemie

0

View full text Add to dashboard Cite

Lanthanide‐containing clusters are synthetically Lanthanide‐containing clusters are synthetically challenging and with significant chemical and materials applications. Herein, two isostructural heterometallic clusters of the formula (NO3)12@[Ln132Ni78(OH)292(IDA)48(CH3COO)96(NO3)12(H2O)78]Cl44·xH2O·yCH3OH (IDA = iminodiacetate; Ln = Gd 1, x = 110, y = 0; Ln = Eu 2, x = 95, y = 40) were obtained via co‐hydrolysis of Ln3+ (Gd3+ or Eu3+) and Ni2+ in the presence of iminodiacetate (IDA). Crystallographic studies show that each features a truncated tetrahedral core of Ln132Ni78 within which a void of 5.5 Å in diameter; connecting the central cage and its exterior are four trumpet‐like passageways surface‐decorated with dinuclear units of [Gd(μ3‐OH)2Gd]. Mass spectroscopic analyses indicate that both clusters maintained their structural integrity in aqueous solution, with cryo‐electron microscopy providing the most convincing visual evidence in support of the cluster's solution stability. Size‐selective Knoevenagel condensation, believed to occur in the passageways on the basis of experimental and molecular modeling results, was achieved in the presence of 1. The application of 1 as a uniquely structured molecular reactor and a recyclable heterogeneous catalyst was further illustrated by the one‐pot three‐component synthesis of biologically and pharmaceutically significant 4H‐pyran derivatives.

show abstract

A Hollowed‐Out Heterometallic Cluster for Catalytic Knoevenagel Condensation

Chen,

Xu,

Qin

et al. 2024

Angew Chem Int Ed

0

View full text Add to dashboard Cite

Lanthanide‐containing clusters are synthetically Lanthanide‐containing clusters are synthetically challenging and with significant chemical and materials applications. Herein, two isostructural heterometallic clusters of the formula (NO3)12@[Ln132Ni78(OH)292(IDA)48(CH3COO)96(NO3)12(H2O)78]Cl44·xH2O·yCH3OH (IDA = iminodiacetate; Ln = Gd 1, x = 110, y = 0; Ln = Eu 2, x = 95, y = 40) were obtained via co‐hydrolysis of Ln3+ (Gd3+ or Eu3+) and Ni2+ in the presence of iminodiacetate (IDA). Crystallographic studies show that each features a truncated tetrahedral core of Ln132Ni78 within which a void of 5.5 Å in diameter; connecting the central cage and its exterior are four trumpet‐like passageways surface‐decorated with dinuclear units of [Gd(μ3‐OH)2Gd]. Mass spectroscopic analyses indicate that both clusters maintained their structural integrity in aqueous solution, with cryo‐electron microscopy providing the most convincing visual evidence in support of the cluster's solution stability. Size‐selective Knoevenagel condensation, believed to occur in the passageways on the basis of experimental and molecular modeling results, was achieved in the presence of 1. The application of 1 as a uniquely structured molecular reactor and a recyclable heterogeneous catalyst was further illustrated by the one‐pot three‐component synthesis of biologically and pharmaceutically significant 4H‐pyran derivatives.

show abstract

Synthetic strategies of pyran derivatives by multicomponent reaction (MCR) approach

Cited by 13 publications

References 149 publications

Copper Schiff base complex immobilized on magnetic graphene oxide: Efficient heterogeneous nanocatalyst for treating environmental pollutants and synthesis of chromenes

Copper Schiff base complex immobilized on magnetic graphene oxide: Efficient heterogeneous nanocatalyst for treating environmental pollutants and synthesis of chromenes

A Hollowed‐Out Heterometallic Cluster for Catalytic Knoevenagel Condensation

A Hollowed‐Out Heterometallic Cluster for Catalytic Knoevenagel Condensation

Contact Info

Product

Resources

About