Biosynthesis of Pd/MnO₂ nanocomposite using Solanum melongena plant extract and its application for the one‐pot synthesis of 5‐substituted 1H‐tetrazoles from aryl halides

Abstract

In this work, for the first time, Solanum melongena plant extract was used for the green synthesis of Pd/MnO 2 nanocomposite via reduction osf Pd(II) ions to Pd(0) and their immobilization on the surface of manganese dioxide (MnO 2 ) nanoparticles (NPs) as an effective support. The synthesized nanocomposite were characterized by various analytical techniques such as Fourier transform infrared (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS) and UV-Vis spectroscopy. The catalytic activity of Pd/MnO 2 nanocomposite was used as a heterogeneous catalyst for the one-pot synthesis of 5-substituted 1H-tetrazoles from aryl halides containing various electron-donating or electron-withdrawing groups in the presence of K 4 [Fe (CN) 6 ] as non-toxic cyanide source and sodium azide. The products were obtained in good yields via a simple methodology and easy work-up. The nanocatalyst can be recycled and reused several times with no remarkable loss of activity. Highlights:• Green synthesis of Pd/MnO 2 nanocomposite using Solanum melongena extract.• Pd/MnO 2 nanocomposite was characterized by FT-IR, XRD, FESEM, EDS and TEM.• One-pot synthesis of 5-substituted 1H-tetrazoles from aryl halides using Pd/MnO 2 nanocomposite.• The catalyst can be easily recycled and reused several times without sensible loss in its catalytic efficiency.

Boehmite@SiO2@ Tris (hydroxymethyl)aminomethane‐Cu(I): a novel, highly efficient and reusable nanocatalyst for the C‐C bond formation and the synthesis of 5‐substituted 1H‐tetrazoles in green media

“…Then, the effect of various bases was investigated and K 2 CO 3 was selected as the most effective base. Moreover, the effect of different temperatures studied, which the reflux condition was selected as the best temperature conditions ( Table 1, entries [19][20][21][22]. As shown in Table 1, aryl halide (1 mmol), phenylboronic acid (1.2 mmol) in the presence of the 0.25 mol % of the catalyst based on Cu loading in EtOH under reflux conditions was found to be the ideal reaction conditions for the formation of the corresponding biphenyl products.…”

“…[13][14][15][16][17][18] Tetrazoles are an important class of heterocyclic compounds. [19][20][21][22] Recently, organic compounds containing tetrazole moiety have attracted increasing attention due to their wide range of applications in various areas of science. [23,24] Especially in medicinal chemistry, [25] tetrazole rings have been utilized as bioisosteres for carboxyl groups owingto their similar properties.…”

“…They have also been used in agrochemicals, as ligands in coordination chemistry, and in materials science. [26] Numerous methods have been developed for the synthesis of tetrazoles, [20,27,28] they have been generally synthesized by [3 + 2]-cycloaddition reaction between nitriles and azides in the presence of various transition metal catalysts, such as Pd, [20,28,29] Ni, [22,30,31] and iron compounds. [32][33][34] Methods for the synthesis of 5-substituted 1H-tetrazoles from aldoximes or aldehydes in the presence of copper (II) catalysts have also been reported.…”

Nanomaterial catalyzed green synthesis of tetrazoles and its derivatives: a review on recent advancements

“…The biocatalyst (Pd/MnO 2 ) offers several advantages like high yields, easygoing preparation, use of K 4 [Fe(CN) 6 ] as a non-toxic cyanide source, simple work-up procedure, escaping formation of destructive hydrazoic acid, and accessibility of MnO 2 as support. 113 A magnetic Fe 3 O 4 @MCM-41-SB-Cu nanocomposite as a catalyst was prepared for 5-substituted-1H-tetrazoles synthesis.…”

Ginkgo biloba leaf polysaccharide stabilized palladium nanoparticles with enhanced peroxidase-like property for the colorimetric detection of glucose

“…19 Barberry fruit extract was used to prepare Pd NPs/RGO by green synthesis to catalyze the reduction of nitroarenes. 20 Many green materials including coffee and tea extract, 21 beet juice, 22 piper longum fruits extract, 23 Euphorbia thymifolia L. leaf extract, 24 Theobroma cacao L. seeds extract, 25 Euphorbia neriifolia L. leaf extract, 26 Gardenia taitensis leaf extract, 27 Solanum melongena plant extract, 28 Cucurbita pepo leaf extract 29,30 have been used to prepare Pd NPs. Ginkgo biloba leaf extract was used as a reducing and stabilizing agent to prepare copper nanoparticles, 31 silver nanoparticles 32 and gold nanoparticles.…”