One-pot Multicomponent Reaction Research Articles

Two Thiophene-Functionalized Co-MOFs as Green Heterogeneous Catalysts for the Biginelli Reaction.

Two Co(II) metal-organic frameworks (Co-MOFs), namely, [Co(DMTDC)(bimb)]n (Co-MOF-1) and {[Co(DPTDC)(bimb)(H2O)]·2DMF}n (Co-MOF-2) (H2DMTDC = 3,4-dimethylthieno[2,3-b]thiophene-2,5-dicarboxylic acid, H2DPTDC = 3,4-diphenylthieno[2,3-b]thiophene-2,5-dicarboxylic acid, bimb = 1,4-bis((1H-imidazol-1-yl)methyl)benzene), were obtained by the reaction of flexible N-containing ligand bimb and two structurally related thiophene-containing ligands H2DMTDC and H2DPTDC, respectively. These Co-MOFs displayed a 3D framework and porous structure, respectively. Co-MOF-1 and the activated sample Co-MOF-2' could act as green heterogeneous catalysts for the one-pot multicomponent Biginelli reaction, specifically the dehydration condensation process involving aldehydes, acetoacetates, and urea to yield dihydropyrimidin-2(1H)-ones. The reaction has advantages such as solvent-free conditions, water as only byproduct, readily accessible starting materials, excellent functional group compatibility, and simple operation. Both catalysts exhibited a wide substrate scope and maintained significant catalytic activity over five cycles. The special catalytic performance may be ascribed to functional groups within the ligand.

Mangrove tree aerial root extract mediated green synthesis of Ag/Fe3O4/rGO nanocomposite and its application as a catalyst for one potsynthesis of 7-phenyl-6H,7H-benzo[4,5]imidazo[2,1-b]chromeno[4,3-d][1,3]thiazin-6-one derivatives.

In this study, we report the green preparation of magnetically separable Ag/Fe3O4/rGO nanocomposites using mangrove tree aerial root extract as a stabilising agent. The morphology, size, chemical composition, magnetic property and other characteristic parameters of synthesised Ag/Fe3O4/rGO nanocomposite were determined by analytical techniques like Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM),transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). The results proved that mangrove tree aerial root extract has the ability to reduce Ag+ ions, graphene oxide (GO) to Ag nanoparticle and reduced graphene oxide (rGO), respectively. The prepared Ag/Fe3O4/rGO nanocomposite was used successfully as a prompt catalyst for synthesis of 7-phenyl-6H,7H-benzo[4,5]imidazo[2,1-b]chromeno[4,3-d][1,3]thiazin-6-one derivatives by one-pot multi-component reaction of 4-hydroxycoumarin (10mmol), 2-mercaptobenzimidazole (10mmol) and different arylaldehyde (10mmol) in the presence of ethanol (10ml) as an eco-benign solvent at reflux condition. By utilising this protocol, we have constructed 7-phenyl-6H,7H-benzo[4,5]imidazo[2,1-b]chromeno[4,3-d][1,3]thiazin-6-one derivatives in good to excellent yield of 80-90%. This synthesis involves the formation of C-C, C-N and C-S bonds. The synthesised organic heterocyclic compounds were examined for the green matrix properties such as atom economy (AE), E-factor and product mass intensity (PMI). This green protocol is of big interest due to employing simple, non-toxic heterogeneous, separable, reusable Ag/Fe3O4/rGO as an eco-safe heterogeneous catalyst and environmentally benign ethanol as a green solvent without the use of any harmful mineral acid and toxic transition metal catalyst.

An Acid-Mediated Multicomponent Domino Reaction for the Synthesis of N-Substituted Isoindolinones

AbstractA one-pot multicomponent reaction of 2-carboxybenzaldehyde, nitriles/anilines and a nucleophile (N,N-disubstituted anilines) for the synthesis of a range of functionalized N-substituted isoindolinone derivatives is described. This metal-free intramolecular cyclization reaction furnishes the desired products in good to excellent yields. The process is environmentally friendly and offers a sustainable method for synthesizing a diverse library of N-substituted isoindolinone derivatives under acidic conditions. This cascade reaction triggers the formation of a C–C and two C–N bonds involving carbonyl and carboxyl groups in the presence of nitriles/anilines. Additionally, in the absence of a nitrogen source, 3-substituted isobenzofuran-1(3H)-ones are synthesized.

Synthesis of dicholesteryl organogelator as a green sorbent nanomaterial for oil spill remediation

In the field of global water purification, the issue of marine oil spills represents a significant challenge. The use of phase-selective organogelators (PSOGs) as sorbent materials in oil spill remediation is a promising solution due to their environmental adaptability and high absorption capacity. However, there are limited reports on PSOGs that can be used in powder form for rapid phase-selective gelation of crude oils. In this context, the development of innovative dicholesteryl derivatives as low-molecular-weight organogelators (LMOGs) offers a promising solution in powder form. These gelators are synthesized through a one-pot multi-component reaction as green synthesis method, which ensures high purity and eliminates the need for harsh conditions. The incorporation of cholesterol into the gelator structure demonstrate environmental adaptability. The exceptional sorption capacity was attributed to the structured 2D/3D networks observed through scanning electron microscopy (SEM). The hydrophobic properties of these gelators, as evidenced by a water contact angle of 118 degrees, enable them to efficiently gel various organic solvents at low concentrations (1% w/v) at ambient temperatures, without the need for heating–cooling cycles or co-solvents. The eco-friendly nature and efficient oil–water separation capabilities of these gelators in powder form represent a significant advancement in global water purification efforts.

Ni-Fe2O3@SiO2-Pr-DBU: A novel efficient magnetically retrievable catalyst for one-pot synthesis of dihydropyrano [3,2-c] chromene

In the present work, Ni-Fe2O3@SiO2-Pr-DBU was synthesized as a novel magnetically separable nano-catalyst and characterized by various techniques like Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), Scanning electron microscopy (SEM), Vibrating-sample magnetometry (VSM), Transmission electron microscopy (TEM) and Elemental analysis by energy dispersive X-ray (EDX). The catalytic efficiency of NiFe2O3@SiO2-Pr-DBU was explored in the synthesis of dihydropyrano[3,2-c] chromenes through a one-pot multicomponent reaction of 4-hydroxycoumarin, malononitrile, and aryl aldehydes in aqueous solution at ambient temperature condition. An external magnet easily removed the nano-sized magnetic core catalyst from the synthesized reaction mixture. It was recycled for five successive runs while maintaining its potential and adhering to our green synthesis approach. We used dihydropyrano chromene, a highly biologically active commercial compound, to prepare some novel derivatives.

Anticancer Activity of 4-Aryl-1,4-Dihydropyridines

We have synthesized 22 symmetric and asymmetric 4-aryl-1,4-dihydropyridines (1,4-DHPs) by a “green” microwave-assisted one-pot multicomponent Hantzsch reaction and evaluated their cytotoxicity to three human cancer cell lines regarding U-251MG (human glioblastoma), HeLa 229 (human cervical adenocarcinoma), and MCF-7 (human breast carcinoma). None of the 1,4-DHPs were cytotoxic to U-251MG cells. Most of the 1,4-DHPs did not affect HeLa 229 or MCF-7 cell viability. On the other hand, symmetric 1,4-DHPs 18 (diethyl 4-(4-benzyloxyphenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate), 19 (diethyl 4-(4-bromophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate), and 20 (diethyl 4-(3-fluorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate) reduced the HeLa (IC50 = 3.6, 2.3, and 4.1 µM, respectively) and MCF-7 (IC50 = 5.2, 5.7, and 11.9 µM, respectively) cell viability. These 1,4-DHPs were more cytotoxic to the HeLa and MCF-7 cells than to the GM07492 (normal human fibroblast) cells, as evidenced by their selectivity indexes. Therefore,1,4-DHPs 18, 19, and 20 may serve as novel lead compounds to discover other 1,4-DHP derivatives with improved anticancer potency and selectivity.

Facile one-pot synthesis of N-pyridinylaminonaphthol derivatives and their antibacterial evaluation against multidrug-resistant Staphylococcus aureus.

The escalating severity of the menace posed by bacterial resistance has rendered the existing antibiotics less effective, thus necessitating the discovery of new antibacterial agents. The current study reports the exploration of substituted N-pyridinylaminonaphthols produced by a straightforward, one-pot multicomponent reaction process as antibacterial agents. The synthesized derivatives were assessed in vitro for their antibacterial properties against a panel of bacterial pathogens. The analogs 4b, 4g, 4h, 4i, 4j, 4l, 4r, and 4t exhibited potent inhibitory activity with minimum inhibitory concentration (MIC) values of 1-2 µg/mL. Notably, 4b, 4l, and 4t displayed an excellent selectivity index. Additionally, they were active against the multidrug-resistant bacterial strains, with 4l exhibiting the best activity against methicillin-resistant Staphylococcus aureus and vancomycin resistant staphylococcus aureus with a MIC of 1 µg/mL. 4l showed synergism with gentamycin and showed bactericidal property in a concentration-dependent manner. Furthermore, the molecule 4l inhibited the DNA gyrase supercoiling activity. Absorption, distribution, metabolism, excretion/toxicity parameters and pharmacokinetic properties were assessed via in silico techniques, which elucidate the potential mode of action. These findings demonstrate the potential of the N-pyridinylaminonaphthol derivatives as antibacterial agents against multidrug-resistant S. aureus.

Green Chemistry and In silico Techniques for Synthesis of Novel Pyranopyrazole and Pyrazolo-pyrano-pyrimidine Derivatives as Promising Antifungal Agents.

Every year Invasive Fungal Infections (IFI) are globally affecting millions of people. Candida albicans and Aspergillus niger have been reported as the most infectious and mortality-inducing fungal strains among all pathogenic fungi. To tackle this problem in the current study Pyranopyrazoles and Pyrazolopyrano- pyrimidine derivatives were developed using molecular hybridization, green chemistry and one-pot multicomponent reaction. In the present work, New Chemical entities (NCE's) were developed on the basis of Structure activity relationship. All designed NCE's were screened for ADMET studies using the QikProp module of Schrodinger software. NCE's with zero violations were further docked on the crystal structure of 14α demethylase, cytochrome P450 and thymidine synthase (PDB ID: 5V5Z, 7SHI, 1BID). Selected molecules were synthesized using green chemistry techniques and evaluated for in vitro antifungal activity against Candida albicans and Aspergillus niger. Designed NCE's (B1-12 and C1-11) showed favorable results in ADMET studies. In the docking study six compounds from series-B and five molecules from series- C showed good dock score and binding interaction when compared with the standard drugs. Compounds B-3 and C-4 showed the highest zone of inhibition activity against Candida albicans, where as B-1 and C-3 had shown highest zone of inhibition activity against Aspergillus niger. Bicyclic ring (series B) showed better activity as compare to fused tricyclic ring (series C).

WITHDRAWN: Green Synthesis and Evaluation of the Biological Activity of New Dihydropyridine Derivatives

It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication.

Enhanced Catalytic Activity of Binuclear Oxidovanadium(IV) Bisbenzimidazole Linked Porphyrin Dimer for the Generation of Biologically Active 3,4-Dihydropyrimidinones and Their Corresponding Thiones.

Binuclear vanadyl(IV) porphyrin (V2BP), where two vanadium(IV) porphyrin macrocycles are linked through benzimidazole units at the β-positions, has been prepared and characterized with various techniques, such as UV-vis, Fourier transform-infrared, electron paramagnetic resonance, cyclic voltammetry, density functional transform calculations, and mass spectrometry. V2BP exhibits a red shift (Δλmax = 10 nm) in the Soret band as compared with unsubstituted parent vanadyl(IV) meso-tetraphenylporphyrin (VP). The synthesized binuclear vanadyl(IV) porphyrin (V2BP) has further been studied as a catalyst to explore a single-pot multicomponent Biginelli reaction producing biologically active 3,4-dihydropyrimidin-2-(1H)-one (DHPM)-based biomolecules and the corresponding thiones under solvent-free conditions and its catalytic activity has been compared with vanadyl(IV) meso-tetraphenylporphyrin (VP). Several reaction conditions, such as the amount of catalyst, time, solvent, and temperature, have been optimized to obtain the maximum yield of DHPMs or thiones. The synthesized β-functionalized V2BP porphyrin dimer manifests much higher conversion (84-95% yield) of DHPMs or the corresponding thiones under the optimized reaction conditions with high TON (4454-5037) and TOF (1113-1259 h-1) values for the one-pot multicomponent Biginelli reaction as compared to the literature. The catalyst exhibited excellent recyclability up to 10 cycles.

Green and Convenient Synthesis of Pharmaceutically Active Mono and Bis-dihydroquinazolines via a One-pot Multicomponent Reaction Under Sulfamic Acid Catalysis

Introduction: Multicomponent reactions (MCRs) and green chemistry are essential criteria for the development of efficient chemical syntheses for valuable organic compounds. Method: The design, synthesis, and development of sustainable procedures for the production of novel biological and pharmaceutical molecules have gained high importance. Herein, an environmentally benign synthesis of mono- and bis-2,3-dihydroquinazolin-4(1H)-ones as pharmaceutically active compounds was carried out in good to high yields of 80-99% within 45-120 minutes. Result: The desired products were synthesized via three-component and pseudo five-component condensations of isatoic anhydride, a primary amine (aniline or ammonium acetate), and an aldehyde/dialdehyde using sulfamic acid (20%) as a solid acidic catalyst under the solvent-free condition at 100°C. Conclusion: The easy work-up procedure, metal-free and environmentally benign catalyst, green reaction conditions for performing MCRs, and high yields of pure products are some advantages of the presented protocol.

Ultrasound Assisted and SO4-2/SnO2-Catalyzed One-Pot Multicomponent Reaction for the Synthesis of 1,2,3,4,6-Pentasubstituted Piperidines

Ultrasound Assisted and SO4-2/SnO2-Catalyzed One-Pot Multicomponent Reaction for the Synthesis of 1,2,3,4,6-Pentasubstituted Piperidines

Synthesis of Polysubstituted Pyridines via Nitrogen-doped Graphene Catalyzed One-Pot Multicomponent Reaction under Solvent-Free Conditions

Abstract: Polysubstituted pyridine derivatives were produced with high to excellent yields in the presence of nitrogen-doped graphene (NDG) as a dual acid-based catalyst. NDG efficiently catalyzes the multicomponent reaction between arylaldehydes, diethyl-acetylene dicarboxylates, malononitrile, and ammonium acetate under solvent-free conditions at 80°C to afford the polysubstituted pyridines in short reaction times. The structures of the synthesized pyridines were established by Ft-IR, 1H, and 13C NMR spectroscopic analysis. The advantages of this method include the in-situ oxidation of prepared 1,4-dihydropyridines, one-pot procedure, solventless system, operational simplicity, and no column chromatography. Additionally, neither toxic solvents nor catalysts are needed, and the procedure can be very reliable among the reported methodologies. The yields and reaction times in the presence of four times recycled catalyst are in comparable to the fresh catalyst.

Synthesis and biological evaluation of new 2-Amino-7-hydroxy-8-methyl-4-aryl-4H-chromene-3-carbonitrile derivatives

A series of new 2-amino-7-hydroxy-8-methyl-4-aryl-4H-chromene-3-carbonitrile derivatives (4a-4g) have been synthesized by a one-pot multicomponent reaction of 2-methylresorcinol (1) and malononitrile (2) with various aldehydes (3). All the synthesised compounds (4a-4g) have been characterised using FT-IR, 1H NMR, 13C NMR, HR-MS and evaluated for swarming behaviour, biofilm formation, biofilm disruption and urease activity against P. mirabilis (MTCC-425). Among all the synthesized compounds, compounds 4a, 4b and 4g showed slightly inhibited swarming behaviour and compounds 4f and 4g inhibited biofilm formation with increasing concentration. SEM (Scanning Electron Microscope) imaging shows that compound 4e effectively disrupts the preformed biofilm. Also, compounds 4d and 4e showed 40% reduction in urease activity. The SAR studies of synthesized compounds are elaborated in detail to provide key structural features. Furthermore, molecular docking studies against urease could provide a mechanistic basis for the inhibition. The per-residue interaction analysis suggested the involvement of non-bonded and bonded interactions with the active site of urease. Hence, the aim of the below study was to synthesize new chromene derivatives and study their biological activities.

Organoselenium-Catalyzed C2,3-Diarylation of N-H Indoles.

An organoselenium-catalyzed C2,3-diarylation of unprotected N-H indoles with electron-rich aromatics has been developed. This one-pot multicomponent tandem cross-dehydrogenation coupling reaction allows for the incorporation of two different aromatic groups to indoles. More importantly, this approach offers significant advantages, including a high atom and step economy, eliminating the need for prepreparation of the reaction substrates, streamlining the synthetic process and enhancing its practicality. Overall, this organoselenium-catalyzed C2,3-diarylation reaction presents an efficient and versatile strategy for the functionalization of indole derivatives.

One-pot multicomponent reaction: An efficient synthesis of 4-(HET)Aryl-substituted pyrazolo-quinolinones.

Pyrazolo-quinolinones (PQs) are a versatile class of Organic chemistry and it was found that they have very advanced functionally promising as selective compounds due to their scaffold and demonstrated low toxicity and considerable clinical promise. Moreover, these compounds have an important role in different applications such as analytical reagents, technical, pharmaceutical development, and biological markers. So, we aimed to synthesize and characterize new 4-(Het)aryl-substituted Pyrazole-quinolinones. Synthesis of One-Pot Multicomponent Reaction was carried out with the reaction of 5-amino-3-methyl-1H-pyrazole 1a, and 5-amino-3-phenyl-1H-pyrazole 1b and dimedone 2 with some (het)aryl aldehydes 3 using ethanol. Characterizations such as the linear structures and the regiospecificity of the reactions were determined by using NMR, GC-MS, IR, and UV measurements. This research will be very useful for all methods and procedures using multi-one-point reactions which are very popular in the synthesis of heterocyclic systems for pyrazole- quinoline skeleton synthesis.

TCS/ZnCl2 as a controlled reagent for the Michael addition and heterocyclic cyclization based on the phenyl pyrazolone scaffold with docking validation as a Covid-19 protease inhibitor

TCS/ZnCl2 is presented as a new catalyst for achieving the Michael addition adduct 5a-g by the reaction of phenyl pyrazolone 4 as the Michael donor and arylidene derivatives 3a-g as the Michael acceptor. The one-pot multi-component reaction of the same fragments' scaffolds as aldehydes 1a-g, malononitrile (2), and phenyl pyrazolone 4 with the same catalyst gives pyrano[2,3-c]pyrazole derivatives 6a-g as final products. The prepared compounds undergo docking validation as COVID-19 protease inhibitors and are compared with hydroxychloroquine as a reference drug. KEY WORDS: Pyranopyrazole, multi-component reactions, TCS/ZnCl2 catalyst, COVID-19, the energy score, hydroxychloroquine Bull. Chem. Soc. Ethiop. 2024, 38(4), 1119-1127. DOI: https://dx.doi.org/10.4314/bcse.v38i4.24

A efficient, regioselective and solvent free synthesis of 5,9-dihydropyrimido[4,5-e][1,2,4]triazolo[1,5-a]pyrimidine-6,8(4H,7H)-diones derivatives in presence nanocatalyst sulfuric acid grafted with silica-3-aminotriazol

In this research, SO3H-functionalized Silica grafted 3-amino triazol has been prepared and identified through FT-IR, XRD, EDX, Fe-SEM, and TGA spectra. 3-chloropropyltriethoxysilane was first reacted with silica nanoparticles and then treated with 3-amino-1H-1,2,4-triazoles and grafted finally with chlorosulfonic acid to prepare SiO2@(CH2)3-AT/SO3H (SNPS-AT/SO3H). Afterward, the catalytic efficiency has been investigated as a homogeneous and recyclable catalyst for the solvent-free synthesis of 5,9-dihydropyrimido[4,5-e][1,2,4]triazolo[1,5-a]pyrimidine-6,8(4H,7H)-diones by the one-pot multi-component reaction of aromatic aldehydes with 3-amino-1H-1,2,4-triazoles and 1,3-dimethyl barbituric acid under thermal (100 °C) conditions.

CuPd bimetallic nanoparticles supported magnetic ionic liquid-derived N-doped carbon as a highly efficient heterogeneous catalyst for the one-pot oxidative multicomponent reactions

BackgroundMulticomponent reactions often rely on aldehydes as the reactants, limiting their widespread use. To enhance the versatility and scope of these reactions, aldehydes can be replaced with alcohols. MethodsIn this study, nitrogen-doped magnetic carbon nanostructures modified with imidazolium-based ionic liquid (Fe3O4@NC-IL) were prepared. These nanostructures were synthesized by a one-pot hydrothermal carbonization method using ferric chloride in the presence of glucose, urea, epichlorohydrin and 1-methylimidazole as carbon source, nitrogen source, linker and ionic liquid, respectively. Then, CuPd bimetallic nanoparticles were immobilized on the synthesized nanostructures by a wet chemical reduction process. Significant findingsThe catalytic activity of the nanostructures was evaluated in the oxidation of alcohol under base-free conditions. The results indicate that the CuPd bimetallic catalyst exhibited better catalytic performance than both Cu and Pd monometallic catalysts, suggesting a synergistic effect between copper and palladium. Also, a non-ionic liquid-based catalyst was synthesized and used in the model reaction to study the effect of imidazolium ionic liquid species on the catalytic activity. The results showed that these species enhanced the catalytic activity. Finally, the catalytic activity of the synthesized structure was evaluated through a one-pot tandem oxidative synthesis of dihydropyrimidinones (Biginelli reaction) and dihydropyridines (Hantzsch reaction).

Polymer Supported Nitrogen-Bridged Symmetrical Binuclear Dioxidomolybdenum(VI) Complexes and Their Homogeneous Analogues as Potential Catalysts for Efficient Synthesis of 2-Amino-3-Cyano-4H-Chromenes/Pyrans.

Reaction of 2-chloromethyl-1H-benzimidazole with known intermediates (i-iii), prepared from diaminoguanidine hydrochloride with salicylaldehyde, 5-bromosalicylaldehyde or 3,5-di-tert-butylsalicylaldehyde, in the presence of triethylamine (NEt3) led to the formation of benzimidazole appended new ligands, H4L1-H4L3 (I-III). The homogeneous nitrogen-bridged symmetrical binuclear complexes, [(MoVIO2)2(L1)(H2O)2] (1), [(MoVIO2)2(L2)(H2O)2] (2) and [(MoVIO2)2(L3)(MeOH)2] (3) have been isolated by reacting these ligands with [MoVIO2(acac)2] in a 1 : 2 molar ratio in refluxing methanol. Using 1 : 1 (ligand to Mo precursor) molar ratio under above reaction conditions resulted in the corresponding mononuclear complexes, [MoVIO2(H2L1)(MeOH)] (4), [MoVIO2(H2L2)(H2O)] (5) and [MoVIO2(H2L3)(MeOH)] (6). The binuclear heterogeneous compounds [(MoVIO2)2(L1)(DMF)2]@PS (PS-1), [(MoVIO2)2(L2)(DMF)2]@PS (PS-2) and [(MoVIO2)2(L3)(DMF)2]@PS (PS-3) have been obtained by immobilization of 1-3 onto chloromethylated polystyrene (PS) beads. All synthesized ligands, homogeneous as well as supported compounds have been characterized by elemental analyses and various spectroscopic methods. Single crystal X-ray diffraction study of complexes 1 and 3 confirms their nitrogen-bridged symmetrical binuclear structures while 4 is mononuclear. Heterogeneous compounds (PS-1-PS-3) have further been studied by microwave plasma atomic emission spectroscopy, X-ray photoelectron spectroscopy, and field emission scanning electron microscopy along with energy dispersive spectroscopy. These compounds (homogeneous and heterogeneous) were explored for catalytic applications to one-pot multicomponent reactions (MCRs) for efficient synthesis of biologically active 2-amino-3-cyano-4H-chromenes/pyrans (21 examples). Optimising various reaction parameters helped in achieving as high as 97 % yields of products. Though, only half equivalent of the binuclear complexes (1-3) was required compared to mononuclear analogues (4-6) to achieve comparable yields, heterogeneous catalysts have an added advantage due to their stability and recyclability. Suitable reaction mechanism has also been proposed based on isolated intermediates.