KCC-1-nPr-NH-Arg as an efficient organo-nanocatalyst for the green synthesis of 1,8-dioxo decahydroacridine derivatives

In the present work, an innovative biocompatible heterogeneous organo-nanocatalyst is prepared based on the grafting of arginine amino acid on the channels and pores of dendritic fibrous nano silica (DFNS). The designed organo-nanocatalyst (KCC-1-nPr-NH-Arg) was characterized by using Field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray spectroscopy (EDS), map analysis, and adsorption/desorption (BET-BJH) instruments. The results of analysis shown that the engineered catalyst has uniform fibrous spheres and dendritic structure with high surface area (178 m² /g) and great pore volume (0.35 cm³ .g^-1 ). Because of exceptional dendritic structure of the engineered organo-nanocatalyst, the active sites are available and the dispersion and adsorption capacity of the reagents and products increase in the pores and channels of the catalyst. Hence, KCC-1-nPr-NH-Arg was used as an capable heterogeneous basic nanocatalyst in the synthesis of 1,8-dioxo decahydroacridine derivatives from the one-pot four component reactions of aromatic aldehydes, dimedone, and ammonium acetate in solvent free conditions with shorter reaction times (13-35 min) and higher yields (94-98%) in evaluation with other reported works. It is expected that, the engineered green organo-nanocatalyst can be used to synthesize other organic compounds. This article is protected by copyright. All rights reserved.

One-pot synthesis of 1,8-dioxodecahydroacridines by using Ag-TiO2 nanocomposite as a mild and heterogeneous catalytic system

Abstract:

Ag-TiO2 nanocomposite was displayed to be an efficient, active, and benign recyclable catalyst for the highly efficient synthesis of 1,8-dioxodecahydroacridine derivatives from dimedone, aromatic aldehydes, and several anilines or ammonium acetate in ethanol as a solvent at room temperature in short reaction time and suitable yield. This catalyst was effortlessly recycled by simple filtration and was reused up to five times with only a negligible loss in its catalytic effectiveness. This process showed substantial advantages containing low loading of the catalyst, cost-effectively mild conditions, purification of target molecules by non-chromatographic technique, worthy atom economy, informal process, application of cheaply available nanocomposite catalyst, use of economical and recyclability of the catalyst. AFM analysis was also attained to confirm the structure topography and morphology of Ag-TiO2 nanocomposite. Natural significance 1,8dioxodecahydroacridine derivatives have a wide range of pharmacological activities for instance antibacterial, antimalarial, anticancer, and mutagenic properties. This method achieves has a varied scope regarding the difference in the aldehydes and anilines.

Introduction of TiO2-[bip]-NH2+ C(NO2)3− as an effective nanocatalyst for the Hantzsch reactions

A novel reagent represented by TiO2-[bip]-NH2+ C(NO2)3− was synthesized, characterized and used as an efficient and reusable nanocatalyst in the synthesis of hexahydroquinoline and 1,8-dioxo-decahydroacridine derivatives.

Incorporation of Keggin-based H3PW7Mo5O40 into bentonite: synthesis, characterization and catalytic applications

The Keggin-based molybdo-substituted tungstophosphoric acid, H3[PW7Mo5O40]·12H2O, were synthesized and incorporated with a bentonite clay by using a wetness impregnation method. The catalysts were characterized using several methods, such as inductively coupled plasma-atomic emission spectroscopy (ICP-AES), Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), scanning electron microscopy energy-dispersive X-ray spectroscopy (SEM-EDS), transmission electron microscopy (TEM), and thermogravimetric and differential thermal analysis (TG-DTA). This extremely active catalytic system provides a green strategy for the synthesis of 1,8-dioxo-octahydroxanthene and 1,8-dioxo-decahydroacridine derivatives under solvent free conditions at 80 °C with a good reaction mass efficiency, effective mass yield, and excellent atom economy. Both the surface acidity and catalytic activity sharply increased after H3[PW7Mo5O40]·12H2O was impregnated with bentonite clay. In addition, the PW7Mo5/bentonite catalyst can be conveniently recovered and reused numerous times without demonstrating a significant loss in activity.

Dendrons containing boric acid and 1,3,5-tris(2-hydroxyethyl)isocyanurate covalently attached to silica-coated magnetite for the expeditious synthesis of Hantzsch esters

A new multifunctional dendritic nanocatalyst containing boric acid and 1,3,5-tris(2-hydroxyethyl)isocyanurate covalently attached to core-shell silica-coated magnetite (Fe3O4@SiO2@PTS-THEIC-(CH2)3OB(OH)2) was designed and properly characterized by different spectroscopic or microscopic methods as well as analytical techniques used for mesoporous materials. It was found that the combination of both aromatic π-π stacking and boron-oxygen ligand interactions affords supramolecular arrays of dendrons. Furthermore, the use of boric acid makes this dendritic catalyst a good choice, from corrosion, recyclability and cost points of view. The catalytic activity of Fe3O4@SiO2@PTS-THEIC-(CH2)3OB(OH)2, as an efficient magnetically recoverable catalyst, was investigated for the synthesis of polyhydroacridines (PHAs) as well as polyhydroquinolines (PHQs) via one-pot multicomponent reactions of dimedone and/or ethyl acetoacetate, different aldehydes and ammonium acetate in EtOH under reflux conditions. Very low loading of the catalyst, high to quantitative yields of the desired PHAs or PHQs products, short reaction times, wide scope of the substrates, eliminating any toxic heavy metals or corrosive reagents for the modification of the catalyst, and simple work-up procedure are remarkable advantages of this green protocol. An additional advantage of this magnetic nanoparticles catalyst is its ability to be separated and recycled easily from the reaction mixture with minimal efforts in six subsequent runs without significant loss of its catalytic activity. This magnetic and dendritic catalyst can be extended to new two- and three-dimensional covalent organic frameworks with different applications.

Bio-assisted synthesized Ag(0) nanoparticles stabilized on hybrid of sepiolite and chitin: efficient catalytic system for xanthene synthesis

In this work, with the use of two natural compounds, chitin and sepiolite clay, a novel covalent hybrid is fabricated and applied as a support for the stabilization of silver nanoparticles with the aid of Kombucha extract as a natural reducing agent. The resultant catalytic system, Ag@Sep-N-CH, was characterized via XRD, TEM, FTIR, ICP, SEM, TGA, UV-Vis and BET. It was found that fine Ag(0) nanoparticles with mean diameter of 6.1 ± 1.8 nm were formed on the support and the specific surface area of the catalyst was 130 m2 g-1. The study of the catalytic performance of Ag@Sep-N-CH for catalyzing synthesis of xanthenes in aqueous media under mild reaction condition confirmed that Ag@Sep-N-CH exhibited high catalytic activity and could promote the reaction of various substrates to furnish the corresponding products in high yields. Moreover, the contribution of both chitin and sepiolite to the catalysis has been affirmed. It was found that hybridization of these two components led to synergistic effects and consequently improved the observed catalytic activity. Notably, the catalyst was recyclable up to several reaction runs.

Organocatalyzed Domino Synthesis of New Thiazole-Based Decahydroacridine-1,8-diones and Dihydropyrido[2,3-d : 6,5-d']- dipyrimidines in Water as Antimicrobial Agents

Organopromoter, 2-aminoethanesulfonic acid was used to catalyze the synthesis of a series of structurally intriguing new hybrids thiazolyl acridine-1,8(2H,5H)-diones and dihydropyrido[2,3-d : 6,5-d']dipyrimidine-2,4,6,8(1H,3H,5H,7H)-tetraones for the first time. 2-Aminoethanesulfonic acid is a biobased organopromoter, used to generate four new bonds for the synthesis of new coupled thiazole-based decahydroacridine-1,8-diones. Superior green credentials, operational simplicity, easy work-up and recyclability of the catalyst are the key strengths of this method. The broad substrate scope, mild reaction conditions, short reaction time, cost effectiveness, high atom economy and good to excellent yields make the present method a distinct improvement over existing methods. Spectral (IR, ¹ H-NMR,¹³ C-NMR, Mass) data and elemental analyses confirmed the structures of the titled products. A series of thiazolyl acridine-1,8(2H,5H)-diones and dihydropyrido[2,3-d : 6,5-d']dipyrimidine-2,4,6,8(1H,3H,5H,7H)-tetraones were screened for their antimicrobial activity against four bacterial and three fungal strains.

Ag Nanoparticles Stabilized on Cyclodextrin Polymer Decorated with Multi-Nitrogen Atom Containing Polymer: An Efficient Catalyst for the Synthesis of Xanthenes

In attempt to broaden the use of cyclodextrin polymer for catalytic purposes, a novel covalent hybrid system was prepared through growth of multi-nitrogen atom containing polymer (PMelamine) derived from reaction of ethylenediamine and 2,4,6-trichloro-1,3,5-triazine on the functionalized cyclodextrin polymer (CDNS). The resulting hybrid system was then utilized as a catalyst support for the immobilization of silver nanoparticles through using Cuscuta epithymum extract as a naturally-derived reducing agent. The catalytic activity of the catalyst, Ag@CDNS-N/PMelamine, for the synthesis of xanthenes through reaction of aldehydes and dimedone in aqueous media was examined. The results showed high catalytic activity and recyclability of the catalyst. It was believed that cyclodextrin in the backbone of the catalyst could act both as a capping agent for Ag nanoparticles and phase transfer agent to bring the hydrophobic substrates in the vicinity of the catalytic active sites and accelerate the reaction rate. Multi-nitrogen atoms on the polymer, on the other hand, could improve the Ag NPs anchoring and suppress their leaching.

Solvent-Free Preparation of 1,8-Dioxo-Octahydroxanthenes Employing Iron Oxide Nanomaterials

In this study, 1,8-dioxo-octahydroxanthenes were prepared employing a simple, effective and environmentally sound approach utilizing an iron oxide nanocatalyst under solventless conditions. The proposed iron oxide nanomaterial exhibited high product yields, short reaction times and a facile work-up procedure. The synthesized catalyst was also found to be highly stable and reusable under the investigated conditions (up to twelve consecutive cycles) without any significant loss in its catalytic activity.

A competent synthesis and efficient anti-inflammatory responses of isatinimino acridinedione moiety via suppression of in vivo NF-κB, COX-2 and iNOS signaling

A potent Nonsterodial Anti-inflammatory Drug (NSAID) candidates has been conceived and built by an assembly of a hydrophilic, fluorescent and COX-2 inhibiting units in the same molecule. The isatinimino-acridinedione core (TM-7) was achieved in a simple three step synthetic procedure viz (i) a multicomponent reaction between dimedone, aldehyde and amine to furnish the nitroacridinedione (4), (ii) reduction step and (iii) schiff's-base condensation with isatin. The excellent anti-inflammatory pharmacological efficiency of the drug was established by in vivo biological experiments. Accordingly, it was found that the treatment with the synthesized isatinimino analogues (dosage: 30 mg/kg) inhibited protein expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and nuclear factor kappa B (NF-κB) as well as production of prostaglandin E2 (PGE2), nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), and interleukin-6 (IL-6) levels induced by carrageenan. Further, a comparative molecular modeling analysis of TM-7 carried out with the crystal structure of aspirin acetylated human COX-2 suggested effectively binding and efficient accommodation inside the active site's gorge.

A facile and efficient synthesis of 1,8-dioxodecahydroacridines derivatives catalyzed by cobalt-alanine metal complex under aqueous ethanol media

A facile and convenient method for the synthesis of acridines and its derivatives was developed through one-pot, three-component condensation reaction of aromatic aldehydes, 5,5-dimethyl-1,3-cyclohexanedione, aryl amines or ammonium acetates in the presence of a catalytic amount of cobalt–alanine metal complex using aqueous ethanol as a reaction medium is reported. The present described novel methodology offers several advantages over the traditional methods reported in the literature, such as mild reaction conditions, inexpensive catalyst, short reaction times, excellent yields of products, simplicity and easy workup are the advantages of this procedure.

Synthesis of sulfamic acid supported on Cr-MIL-101 as a heterogeneous acid catalyst and efficient adsorbent for methyl orange dye

Typical highly porous metal–organic framework (MOFs) materials based on chromium benzenedicarboxylates (Cr-BDC) were prepared through a one-pot hydrothermal synthesis, and were then modified by loading the appropriate ratio of sulfamic acid (SA) using a simple impregnation technique. Pure and modified MIL-101 was characterized by XRD, TEM, SEM and FT-IR measurements. TEM and SEM measurements confirmed that the MIL-101 particles preserved their regular octahedral structure after loading with different weight contents of sulfamic acid. The total number of acid sites and Brønsted to Lewis acid sites ratio (B/L) were examined using potentiometric titration and pyridine adsorption. The acid strength and surface acidity of SA/MIL-101 gradually increased after the modification of Cr-MIL-101 by sulfamic acid crystals up to 55 wt%, then decreased again. The catalytic performance of the solid catalysts was confirmed in the synthesis of 14-phenyl-14H-dibenzo [a,j] xanthene and 7-hydroxy-4-methyl coumarin. In the two reactions, the sample with 55% sulfamic acid loaded on MIL-101 displayed the highest catalytic activity and acidity. The adsorption behaviors of sulfamic acid loaded on MIL-101 materials for methyl orange (MO) as an anionic dye were studied, and were exceptionally suitable for the Langmuir adsorption isotherm. All loaded adsorbents showed high adsorption capacity for methyl orange at 25 °C. The results indicate that the adsorption capacity was modified by changing the amount of sulfamic acid loaded on MIL-101.

Sulfamic acid was incorporated into MIL-101 (Cr). The samples exhibited excellent adsorption performance for MO dye and acted as heterogeneous catalysts for coumarin and xanthene synthesis.

Recent developments on ultrasound-assisted one-pot multicomponent synthesis of biologically relevant heterocycles

Heterocycles are the backbone of organic compounds. Specially, N- &O-containing heterocycles represent privileged structural subunits well distributed in naturally occurring compounds with immense biological activities. Multicomponent reactions (MCRs) are becoming valuable tool for synthesizing structurally diverse molecular entities. On the other hand, the last decade has seen a tremendous outburst in modifying chemical processes to make them sustainable for the betterment of our environment. The application of ultrasound in organic synthesis is fulfilling some of the goals of 'green and sustainable chemistry' as it has some advantages over the traditional thermal methods in terms of reaction rates, yields, purity of the products, product selectivity, etc. Therefore the synthesis of biologically relevant heterocycles using one-pot multi-component technique coupled with the application of ultrasound is one of the thrusting areas in the 21st Century among the organic chemists. The present review deals with the "up to date" developments on ultrasound assisted one-pot multi-component synthesis of biologically relevant heterocycles reported so far.

Fe3O4@SiO2–MoO3H nanoparticles: a magnetically recyclable nanocatalyst system for the synthesis of 1,8-dioxo-decahydroacridine derivatives

Nano Fe₃O₄@SiO₂–MoO₃H is reported as a novel, highly efficient and recyclable heterogeneous nanocatalyst for the synthesis of 1,8-dioxo-decahydroacridine derivatives.

Covalently anchored sulfamic acid on cellulose as heterogeneous solid acid catalyst for the synthesis of structurally symmetrical and unsymmetrical 1,4-dihydropyridine derivatives

A novel heterogeneous solid acid catalyst has been prepared by covalent grafting of chlorosulphonic acid on amino-functionalized cellulose (Cell–Pr-NHSO₃H).

ZnII doped and immobilized on functionalized magnetic hydrotalcite (Fe3O4/HT-SMTU-ZnII): a novel, green and magnetically recyclable bifunctional nanocatalyst for the one-pot multi-component synthesis of acridinediones under solvent-free conditions

Herein, the catalytic activity of a novel synthesized Fe₃O₄/HT-SMTU-Zn^II nanocatalyst, in the green and efficient synthesis of acridinediones, is described.

Cross-dehydrogenative regioselective Csp3–Csp2coupling of enamino-ketones followed by rearrangement: an amazing formation route to acridine-1,8-dione derivatives

A novel route for the construction of acridine-1,8-dione derivatives through CDC coupling of enamino-ketones followed by rearrangement.

Sulfonated carbon/nano-metal oxide composites: a novel and recyclable solid acid catalyst for organic synthesis in benign reaction media

A novel catalytic system based on the use of nano-metal oxides and carbon has been designed and exhibits excellent catalytic activity for acid catalyzed organic reactions.

Water mediated reactions: TiO2and ZnO nanoparticle catalyzed multi component domino reaction in the synthesis of tetrahydroacridinediones, acridindiones, xanthenones and xanthenes

Tetrahydroacridine-1,8-(2H,5H,9H,10H)-diones4from 1,3-cyclohexanedione and/or dimedone 1,2-chloro-3-formylquinoline2and anilines3in water at 90 °C were obtained by domino reaction approach.

Salicyldimine-based Schiff's complex of copper(ii) as an efficient catalyst for the synthesis of nitrogen and oxygen heterocycles

This work deals with the synthesis and characterization of SiO₂–Cu(ii) and its application for the synthesis of aminochromenes and acridinones.

Ammonium Chloride Catalysed One-pot Multicomponent Synthesis of 1,8-dioxo-octahydroxanthenes and N-aryl-1,8-dioxodecahydroacridines Under Solvent Free Conditions

A simple, straight for ward and highly efficient protocol has been developed for the one-pot multicomponent synthesis of 1,8-dioxo-octahydroxanthenes from the reaction of aromatic aldehydes and dimedone, and also N-aryl-1,8-dioxodecahydroacridines from aromatic aldehydes, dimedone and aromatic amines in excellent yields using ammonium chloride as a low-cost and non-toxic eco-friendly catalyst under solvent-free conditions. The salient features of the present protocol are the operational simplicity, clean reaction profiles, excellent yields, high atom-economy, relatively short reaction-time as well as the use of inexpensive and environmentally benign catalyst.