Green and efficient three-component synthesis of 4H-pyran catalysed by CuFe ₂ O ₄ @starch as a magnetically recyclable bionanocatalyst

Abstract

The development of simple, practical and inexpensive catalysis systems using natural materials is one of the main goals of pharmaceutical chemistry as well as green chemistry. Owing to the ability of easy separation of nanocatalyst, those goals could be approached by applying heterogeneous bionanocatalyst in combination with magnetic nanoparticles. Starch is one of the most abundant natural polymers; therefore, preparing bionanocatalyst from starch is very valuable as starch is largely available and inexpensive. An ecologically benign and efficacious heterogeneous nanocatalyst was prepared based on a biopolymer, and its attributes and morphology were specified by using Fourier transform infrared spectra, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), thermal analysis and vibrating sample magnetometer measurements; followed by studying catalytic behaviour of bionanocomposite in a multicomponent reaction to synthesize of 4H-pyran derivatives. 4H-pyran is extremely valuable in pharmaceutical chemistry, and the development of methods for synthesis of different derivatives of 4H-pyran is momentous. Revealing environmentally benign nature, mild condition, easy work-up, low cost and non-toxicity are some of the advantages of this protocol. Besides, the bionanocomposite was recovered using an external magnetic bar and could be re-used at least six times with no further decrease in its catalytic activity.

An overview of recent advances in the catalytic synthesis of substituted pyrans

“…Kamalzare and workers [ 86 ] reported a green method for 4H‐pyran derivatives using CuFe 2 O 4 @starch as a catalyst with EtOH at RT for 20–40 min. Different solvents that were tested such as H 2 O, CH 3 CN, EtOH and EtOH were found suitable for excellent yields (87%–96%).…”

Recent advances in the application of magnetic bio-polymers as catalysts in multicomponent reactions

“…Its catalytic activity was tested in the synthesis of 4 H -chromene 125 or 126 via the three-component reaction of various aldehydes 19, malononitrile 14, 2-hydroxy-1,4-naphthoquinone 123, or 4-hydroxycoumarin 124 ( Scheme 38 ). 68 …”

Synthesis and Reactivity of Copper and Copper Containing Magnetically Separable Catalysts

“…4H-pyran is extremely valuable in pharmaceutical chemistry, such as antifungal, antiviral, antioxidant, antileishmanial, antiallergenic, antibacterial, hypotensive, anticoagulant, diuretic and anti-tumor activities [114] and the development of methods for synthesis of different derivatives of 4H-pyran is momentous. Maleki and co-worker [115] developed a novel and green procedure by studying catalytic behavior of bionanocomposite in a multicomponent reaction for the synthesis of 4H-pyran derivatives.…”

“…4H‐pyran is extremely valuable in pharmaceutical chemistry, such as antifungal, antiviral, antioxidant, antileishmanial, antiallergenic, antibacterial, hypotensive, anticoagulant, diuretic and anti‐tumor activities [114] and the development of methods for synthesis of different derivatives of 4 H ‐pyran is momentous. Maleki and co‐worker [115] developed a novel and green procedure by studying catalytic behavior of bionanocomposite in a multicomponent reaction for the synthesis of 4 H ‐pyran derivatives. Magnetically recyclable nanocatalysts CuFe 2 O 4 @starch was used for the three‐component reaction of the aromatic aldehyde, malononitrile and enolizableC−H activated acidic in ethanol as a solvent to synthesize the said derivatives at room temperature (Scheme 28).…”