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The widespread environmental contamination resulting from the misuse of tetracycline antibiotics (TCs) has garnered significant attention and study by scholars. Photocatalytic technology is one of the environmentally friendly advanced oxidation processes (AOPs) that can effectively solve the problem of residue of TCs in the water environment. This study involved the synthesis of the heterogeneous magnetic photocatalytic material of CoFe2O4/NaBiO3 via the solvothermal method, and it was characterized using different characterization techniques. Then, the photocatalytic system under visible light (Vis) was coupled with peroxymonosulfate (PMS) to explore the performance and mechanism of degradation of tetracycline hydrochloride (TCH) in the wastewater. The characterization results revealed that CoFe2O4/NaBiO3 effectively alleviated the agglomeration phenomenon of CoFe2O4 particles, increased the specific surface area, effectively narrowed the band gap, expanded the visible light absorption spectrum, and inhibited recombination of photogenerated electron–hole pairs. In the Vis+CoFe2O4/NaBiO3+PMS system, CoFe2O4/NaBiO3 effectively activated PMS to produce hydroxyl radicals (·OH) and sulfate radicals (SO4−). Under the conditions of a TCH concentration of 10 mg/L−1, a catalyst concentration of 1 g/L−1 and a PMS concentration of 100 mg/L−1, the degradation efficiency of TCH reached 94% after 100 min illumination. The degradation of TCH was enhanced with the increase in the CoFe2O4/NaBiO3 and PMS dosage. The solution pH and organic matter had a significant impact on TCH degradation. Notably, the TCH degradation efficiency decreased inversely with increasing values of these parameters. The quenching experiments indicated that the free radicals contributing to the Vis+CoFe2O4/NaBiO3+PMS system were ·OH followed by SO4−, hole (h+), and the superoxide radical (O2−). The main mechanism of PMS was based on the cycle of Co3+ and Co2+, as well as Fe3+ and Fe2+. The cyclic tests and characterization by XRD and FT-IR revealed that CoFe2O4/NaBiO3 had good degradation stability. The experimental findings can serve as a reference for the complete removal of antibiotics from wastewater. [ABSTRACT FROM AUTHOR]

The widespread environmental contamination resulting from the misuse of tetracycline antibiotics (TCs) has garnered significant attention and study by scholars. Photocatalytic technology is one of the environmentally friendly advanced oxidation processes (AOPs) that can effectively solve the problem of residue of TCs in the water environment. This study involved the synthesis of the heterogeneous magnetic photocatalytic material of CoFe2O4/NaBiO3 via the solvothermal method, and it was characterized using different characterization techniques. Then, the photocatalytic system under visible light (Vis) was coupled with peroxymonosulfate (PMS) to explore the performance and mechanism of degradation of tetracycline hydrochloride (TCH) in the wastewater. The characterization results revealed that CoFe2O4/NaBiO3 effectively alleviated the agglomeration phenomenon of CoFe2O4 particles, increased the specific surface area, effectively narrowed the band gap, expanded the visible light absorption spectrum, and inhibited recombination of photogenerated electron–hole pairs. In the Vis+CoFe2O4/NaBiO3+PMS system, CoFe2O4/NaBiO3 effectively activated PMS to produce hydroxyl radicals (·OH) and sulfate radicals (SO4−). Under the conditions of a TCH concentration of 10 mg/L−1, a catalyst concentration of 1 g/L−1 and a PMS concentration of 100 mg/L−1, the degradation efficiency of TCH reached 94% after 100 min illumination. The degradation of TCH was enhanced with the increase in the CoFe2O4/NaBiO3 and PMS dosage. The solution pH and organic matter had a significant impact on TCH degradation. Notably, the TCH degradation efficiency decreased inversely with increasing values of these parameters. The quenching experiments indicated that the free radicals contributing to the Vis+CoFe2O4/NaBiO3+PMS system were ·OH followed by SO4−, hole (h+), and the superoxide radical (O2−). The main mechanism of PMS was based on the cycle of Co3+ and Co2+, as well as Fe3+ and Fe2+. The cyclic tests and characterization by XRD and FT-IR revealed that CoFe2O4/NaBiO3 had good degradation stability. The experimental findings can serve as a reference for the complete removal of antibiotics from wastewater.

An efficient and practical catalytic system for the oxidation of alcohols to aldehydes/ketones using catalytic amounts of Bi(NO3)3 and Keto-ABNO (9-azabicyclo [3.3.1]nonan-3-one N-oxyl) with air as the environmentally benign oxidant was developed. Various primary and secondary alcohols were smoothly oxidized to the corresponding products under mild conditions, and satisfactory yields were achieved. Moreover, this methodology avoids the use of a ligand and base. The gram-scale reaction was demonstrated for the oxidation of 1-phenyl ethanol, and the product of acetophenone was obtained at an isolated yield of about 94%. [ABSTRACT FROM AUTHOR]

An efficient and practical catalytic system for the oxidation of alcohols to aldehydes/ketones using catalytic amounts of Bi(NO3)3 and Keto-ABNO (9-azabicyclo [3.3.1]nonan-3-one N-oxyl) with air as the environmentally benign oxidant was developed. Various primary and secondary alcohols were smoothly oxidized to the corresponding products under mild conditions, and satisfactory yields were achieved. Moreover, this methodology avoids the use of a ligand and base. The gram-scale reaction was demonstrated for the oxidation of 1-phenyl ethanol, and the product of acetophenone was obtained at an isolated yield of about 94%.

Herein, Bi(NO 3) 3 was innovatively introduced into the preparation process of MIL-101 (Fe), and the induced structural regulation and its impact on the adsorption-photocatalytic performance for micro-organic contaminants (MCs) were investigated systematically. The results show that, when FeCl 3 was used as an iron source and Bi(NO 3) 3 mol percentage reached 45 %, BiOCl/MIL-88B(Fe) composite heterojunction was formed in situ, showing high adsorption (49.5 %) and removal rate (81.8 % and 91.2 %) after 180 min under visible light and UV irradiation for low concentration tetracycline (TC), respectively. The organics adsorbed on the composite surface could be further decomposed. When Fe(NO 3) 3 was used as the iron source, the introduction of a small amount of Bi(NO 3) 3 (5 %) contributed to the preparation of MIL-88B(Fe/Bi) in situ and the generation of more surface hydroxyl groups. The adsorption and removal rate of TC under visible light reached 68.9 % and 90.8 %, respectively and the generated by-products were also effectively degraded. The in-situ prepared BiOCl/MIL-88B(Fe) heterojunction could effectively promote the separation of photogenerated carriers and the dark generated ·OH and ·O2− could effectively accelerate the adsorption of pollutants. These results have opened up new ideas for the development of novel porous adsorption-photocatalysis materials with a simple preparation process, high efficiency, low cost, and the ability to effectively overcome the mass transfer resistance of MCs. [Display omitted] • Structure regulation of Bi(NO 3) 3 added in MIL-101(Fe) preparation process are studied. • Using FeCl 3 as iron source, BiOCl/MIL-88B(Fe) can be prepared in situ by this method. • Using Fe(NO 3) 3 as iron source, MIL-88B(Fe/Bi) can be successfully prepared in situ. • BiOCl/MIL-88B(Fe) and MIL-88B(Fe/Bi) show superior adsorption-photocatalytic activity. [ABSTRACT FROM AUTHOR]

Three components one-pot Mannich reaction of aromatic ketone, aromatic aldehyde and aromatic amines has been efficiently catalyzed by recyclable bismuth nitrate (Bi(NO3)3, BN) at ambient temperature to give various β-amino carbonyl compounds in high yields. This method has advantages of mild condition, no environmental pollution, and simple work-up procedures. Most importantly, β-amino carbonyl compounds with ortho-substituted aromatic amines are obtained in acceptable to moderate yields by this methodology.

Nitro catechols via 2 hydroxyl group and a nitro group have a wide range of functions including reagents form stable complexes with more than 40 elements in the fields of analytical chemistry, biochemistry, coordination chemistry, environmental chemistry, atrium exploration, organic chemistry, pharmacy, etc. Moreover, the nitro to amine recovery has a potential function in different fields. In recent years the use of various nitration factors including metal nitrates with environmentally friendly features, and in order to reduce pollution as an alternative to nitric acid / sulfuric acid has been reported. High-performance trivalent bismuth nitrate nitration has been reported in the literature. In this work, impregnated nitrate bismuth on solid montmorillonite KSS and KSF in catechol ring nitration was used in conditions of largely different polarity solvents. Under the condition of the use of montmorillonite KSF as the solid phase and dichloromethane solvent, conversion of catechol to nitrate derivatives will be quantitative.

This study developed a novel nitrogen and sulphur co-doped carbon quantum dot-modified bismuth oxide binary composite (N,S-CQD- Bi 2 O 3) through a hydrothermal method. The binary composite was successfully evaluated for its solar light-assisted photocatalytic abatement of toxic refractory pollutants such as dyes (rhodamine B, xylenol orange and sunset yellow), pesticides (2,4-D and diuron) and pharmaceutical drug (tetracycline). It was also successfully applied for the electrochemical detection of aniline molecules. The structural, morphological, optical, and electrochemical properties of the developed photocatalyst were investigated by XRD, FESEM, TEM, UV–vis DRS, XPS, PL, CV, amperometry and impedance techniques. Among the three different weight percentage binary composites, the 5% N,S-CQD-Bi 2 O 3 displayed maximum photocatalytic performance. In all cases, the binary heterojunction exhibited a degradation efficiency of over 90% by converting the harmful compounds into less harmful ones. The scavenger experiments showed the roles of ˙OH and O 2 −˙ radicals in the photodegradation. The improved photocatalytic behaviour was ascribed to the Z-scheme heterojunction formation, enhancements in visible light absorption, improved surface morphology and efficient separation and transfer of electron-hole pairs. The electrochemical detection method yields a LOD of 0.25 nM within the linear range of 5–35 nM. Real sample analysis of aniline also produces excellent results with outstanding reproducibility. [Display omitted] • Rapid and efficient synthesis of N,S-CQD-Bi2O3 by a hydrothermal method. • Photocatalytic activities against Rh B, XO, SY, 2,4-D and diuron. • 5% N,S-CQD-Bi2O3 displayed maximum photocatalytic performance. • GCE/N,S-CQD-BI 2 O 3 based electrochemical detection of aniline with a LOD of 0.25 nM. • Z-scheme photodegradation mechanism was proposed. [ABSTRACT FROM AUTHOR]

Microwave-induced Bi(NO 3 ) 3 -catalyzed one-pot synthesis of a series of linear indoloquinolines is accomplished under mild reaction conditions. While majority of these examples were carried out under solvent-free conditions, in a few cases, minimal quantity of THF is used as solvent. The methodology involves several unique reaction pathways, providing different linear indolo[2,3- b ]quinolines in good yields from readily available starting materials and using environmentally benign Bi(NO 3 ) 3 ·5H 2 O as catalyst. [ABSTRACT FROM AUTHOR]

In this work, thin nanocomposite membranes of polyvinyl alcohol (PVA)/acrylic acid (AAc)/bismuth were synthesized by means of ionizing radiation induced copolymerization of AAc with PVA in the presence of different Bi(NO) concentrations. The prepared nanocomposite membranes were characterized by studying gelation percent, FTIR and water uptake. The nanocomposite formation was confirmed by examining the X-ray diffraction patterns and transmission electron microscope micrographs. The effect of the inclusion of Bi nanoparticles within the prepared membrane on their thermal stability was investigated by thermogravimetric analysis. The electrical resistivity of the prepared nanocomposite membranes were also studied. The results showed that the inclusion of Bi nano particles within the (PVA/AAc) membranes improve their electrical properties such improvement may recommend the prepared nanocomposite to be used in some electrochemical applications. [ABSTRACT FROM AUTHOR]

The Bi(NO3)3.5H2O mediated synthesis of α-hydroxyphosphonates via phosphonylation of aldehydes is reported herein. Both conventional and microwave technology was efficiently applied to range of aromatic, heteroaromatic, α,β-unsaturated aldehydes under solvent-free conditions. The solvent free conditions, avoidance of toxic reagents and excellent yield are some of the remarkable features of this protocol to access the medicinally privileged structure, α-hydroxyphosphonates. [ABSTRACT FROM PUBLISHER]

• Facile synthesis of ternary nanocomposites having different weight percents of MWCNTs. • Characterization using FTIR, SEM, TEM, XRD and TGA techniques. • Increased thermal stability is observed as weight percent of MWCNTs increases. • Pb2+ sensing using cyclic voltammetry. • Plausible mechanism of sensing is discussed. The current work describes a facile synthesis of bismuth molybdosulphosalicylate cation exchanger BiMoS and their polypyrrole (Ppy) nanocomposites incorporating different weight percentages of multiwalled carbon nanotubes (MWCNTs) using sol-gel approach via in-situ oxidative polymerization generating BiMoS-Ppy, BiMoS-Ppy-0.1MWCNTs and BiMoS-Ppy-0.2MWCNTs ternary nanocomposites having zero, 0.1 and 0.2 g weight percent of MWCNTs. These ternary nanocomposites were systematically characterized by FTIR, SEM, TEM, XRD and TGA techniques. The spectral data indicates the successful polymerization of pyrrole on the BiMoS nanoparticles. The TEM images correspondingly signify the encapsulation of BiMoS on the polypyrrole matrix whereas MWCNTs appears as long threads implying successful formation of ternary nanocomposites. The TGA profiles of BiMoS-Ppy, BiMoS-Ppy-0.1MWCNTs and BiMoS-Ppy-0.2MWCNTs are suggestive that as the loading of MWCNTs is increased, the thermal stability also gets increased. Moreover, the BiMoS-Ppy, BiMoS-Ppy-0.1MWCNTs and BiMoS-Ppy-0.2MWCNTs ternary nanocomposites were explored for their possible lead sensing application using cyclic voltammetry. The possible mechanism of Pb2+ion detection in the presence BiMoS-Ppy-0.2MWCNTs ternary nanocomposite was also discussed. [ABSTRACT FROM AUTHOR]

One of the more elusive classes of macrocycles includes the calix[5]pyrroles, which can be obtained from pyrrole and acetone in the presence of low concentrations of Bi(NO3)3-5H2O. An isotopic labeling experiment aided the proposal of a mechanism to explain the formation of calix[5]pyrrole at low acid concentrations and the exclusive formation of calix[4]pyrrole at high acid concentrations. We assume that the mechanism involves HNO3, which is released from the Bi salt.

A convenient and efficient one-pot method for the synthesis of a variety of α-amino nitriles from aldehydes, amines and trimethylsilyl cyanide (TMSCN) in the presence of a catalytic amount of Bi(NO3)3 at room temperature in acetonitrile (MeCN) is described. The significant features of this method are simple work-up procedure, inexpensive and non-toxic catalyst, shorter reaction times and excellent product yields. The catalyst Bi(NO3)3 can be reused. The reusability of the catalyst has been studied for the synthesis of various amino nitriles.

Bismuth nitrate catalyzed efficient Hantzsch reaction via four-component coupling reactions of aromatic aldehydes, 5,5-dimethyl-1,3-cyclohexanedione (dimedone), ethyl acetoacetate and ammonium acetate at 80 °C temperature was described as the preparation of 1,4-dihydropyridine derivatives. 2-Amino-4-phenyl-3-cyano-7,7-dimethyl-5-oxo-1,4,5,6,7,8-hexahydroquinoline derivatives are also prepared under the same experimental conditions using aldehydes, dimedone, malononitrile and ammonium acetate in good yield. The higher catalytic activity of Bi(NO3)·5H2O is ascribed to its high acidity, thermal stability and water tolerance. The process presented here is operationally simple, environmentally benign and has excellent yield. Furthermore, the catalyst can be recovered conveniently and reused efficiently.

The classical Hantzsch reaction is one of the simplest and most economical methods for the synthesis of biologically important and pharmacologically useful 1,4-dihydropyridine derivatives. Bismuth nitrate pentahydrate under microwave irradiation is proven to act as a very efficient catalyst for a one-pot, three-component synthesis of 1,4-dihydropyridines in excellent yields from diverse amines/ammonium acetate, aldehydes and 1,3-dicarbonyl compounds within 1–3 min under solvent-free conditions. The present environmentally benign procedure for the synthesis of 1,4-dihydropyridines is suitable for library synthesis and it will find application in the synthesis of potent biologically active molecules. The excellent yield and extreme rapidity of the method is due to a concurrent effect of the catalyst and microwave irradiation.

The one-pot synthesis of novel 3-(arylamino)-5,8-diaryl-1-hydroxy- N 2 , N 6 -diphenylbicyclo[2.2.2]oct-2-ene-2,6-dicarboxamides in good yields has been accomplished via the multicomponent reaction of aromatic aldehydes, substituted anilines, and acetoacetanilide using bismuth nitrate as a catalyst. [ABSTRACT FROM AUTHOR]

A highly efficient and versatile catalytic system for oxidation of primary and secondary aromatic alcohols to carbonyls has been developed. High efficiency, general synthetic applicability, broader functional group tolerance and versatility towards oxidation of both primary and secondary aromatic alcohols are the key features of this green and sustainable protocol. Selective oxidation of 5-hydroxymethyl furfural (HMF) to biofuel 2,5-diformylfuran (DFF) has been observed in excellent yields. Use of sustainable bio-polymer cellulose as a Cu-nanoparticle support makes the catalytic system environmentally benign. [ABSTRACT FROM AUTHOR]

Three components one-pot Mannich reaction of aromatic ketone, aromatic aldehyde and aromatic amines has been efficiently catalyzed by recyclable bismuth nitrate (Bi(NO 3 ) 3 , BN) at ambient temperature to give various β-amino carbonyl compounds in high yields. This method has advantages of mild condition, no environmental pollution, and simple work-up procedures. Most importantly, β-amino carbonyl compounds with ortho -substituted aromatic amines are obtained in acceptable to moderate yields by this methodology. [ABSTRACT FROM AUTHOR]

Bi(NO3)3, a low-cost, mild, and environmentally green catalyst, has been successfully utilized for Fischer glycosylation for the synthesis of alkyl/aryl glycopyranosides by reacting unprotected sugars, namely, D-glucose, L-rhamnose, D-galactose, D-arabinose, andN-acetyl-D-glucosamine with various alcohols in good to excellent yields. The glycosides were formed with high α-selectivity. Further, an expedient separation of α- and β-glycosides using silver nitrate–impregnated silica gel flash liquid chromatography has been developed. [ABSTRACT FROM AUTHOR]

Abstract: Direct nitration of estradiol was carried out using metal nitrates on solid surfaces under mild condition, and a combination of bismuth nitrate pentahydrate impregnated KSF clay was found to be the best reagent to synthesize 2- and 4-nitroestradiol effectively. Furthermore, various basic side chains were introduced, through O-linker at C-3, to these nitroestradiols. The ability of these derivatives to cause cytotoxicity in Estrogen Receptor (ER)-positive and ER-negative breast cancer cell lines, as well as cancer cell lines of other origins, was examined. Qualitative structure activity relationship (SAR) has also been studied. We found that a basic side chain containing either a piperidine or morpholine ring, when conjugated to 2-nitroestradiol, was particularly effective at causing cytotoxicity in each of the cancer cell lines examined. Surprisingly, this effective cytotoxicity was even seen in ER-negative breast cancer cells. [Copyright &y& Elsevier]

Abstract: An efficient and one-pot synthetic method for the regioselective ortho-nitration of the N-phenyl carboxamides and primary anilines has been developed by using bismuth nitrate and acetic anhydride as the nitrating reagents. Reaction proceeds at room temperature and results in corresponding ortho-nitrated products in moderate to excellent yields. This method provides an operationally simple, regioselective, and efficient access to synthesize o-nitro anilines under the mild conditions. [Copyright &y& Elsevier]

One of the more elusive classes of macrocycles includes the calix[5]pyrroles, which can be obtained from pyrrole and acetone in the presence of low concentrations of Bi(NO3)3-5H2O. An isotopic labeling experiment aided the proposal of a mechanism to explain the formation of calix[5]pyrrole at low acid concentrations and the exclusive formation of calix[4]pyrrole at high acid concentrations. We assume that the mechanism involves HNO3, which is released from the Bi salt. [ABSTRACT FROM AUTHOR]

One of the more elusive classes of macrocycles includes the calix[5]pyrroles, which can be obtained from pyrrole and acetone in the presence of low concentrations of Bi(NO3)3-5H2O. An isotopic labeling experiment aided the proposal of a mechanism to explain the formation of calix[5]pyrrole at low acid concentrations and the exclusive formation of calix[4]pyrrole at high acid concentrations. We assume that the mechanism involves HNO3, which is released from the Bi salt. [ABSTRACT FROM AUTHOR]

Abstract: A series of doubly-propargylated N-methylcarbazole and carbazole derivatives were synthesized in good to excellent isolated yields in (bmim)PF6 using triflic acid (10mol%). The use of bismuth nitrate (20mol%) instead of triflic acid allowed stepwise propargylation employing two different propargylic alcohols, to prepare mixed bis-propargylated carbazoles. Simple product isolation, mild reaction conditions, and repeated recycling and reuse of (bmim)PF6 are added advantages of this IL-mediated synthetic method. [Copyright &y& Elsevier]

Abstract: Highly stereoselective synthesis of 3-pyrrole substituted β-lactams is accomplished. The first step involves the synthesis of 3-phthalimido substituted β-lactams following Staudinger cycloaddition reaction of acid chloride equivalent with imines. Synthesis of 3-amino β-lactams is achieved via the deprotection of phthalimido group with ethylenediamine. These 3-amino β-lactams are converted to a new series of N-substituted pyrroles at room temperature as well as using microwave-induced bismuth nitrate-catalyzed reaction with an excellent yield. Exclusive formation of trans pyrrole-substituted β-lactams is observed with N-chrysenyl system. The method is equally efficient for the synthesis of racemic as well as optically pure 3-pyrrole substituted β-lactams. [Copyright &y& Elsevier]

Abstract: A suspension of bismuth nitrate pentahydrate (BN) in [bmim][PF6] or [bmim][BF4] imidazolium ionic liquid (IL) is an effective reagent for ring nitration of activated aromatics under mild conditions without the need for external promoters. Nitration can also be effected in 1,2-DCE, MeCN, or MeNO2 without additives. Nitration of activated arenes (anisole, toluene, ethylbenzene, cumene, p-xylene, mesitylene, durene, and 1,3-dimethoxybenzene) is considerably faster (time to completion) in BN/[bmim][PF6] relative to BN/1,2-DCE and there are also differences in isomer distributions (for anisole, toluene, and ethylbenzene). With introduction of strongly deactivating substituents (–CHO; –MeCO; –NO2) the BN/IL system is no longer active but reactions still proceed with BN/1,2-DCE in reasonable yields. The ready availability and low cost of BN, simple operation, and absence of promoters, coupled to recycling and reuse of the IL, provide an attractive alternative to classical nitration methods for activated arenes. Switching from Bi(NO3)3·5H2O/[bmim][PF6] to Bi(NO3)3·5H2O/1,2-DCE increases the scope of the substrates that can be nitrated. [Copyright &y& Elsevier]

Abstract: Propargylation of a variety of substituted indoles as well as mono- and di-propargylation of carbazole are achieved in 80–94% isolated yields by employing catalytic amounts (10mol%) of the readily available Bi(NO3)3·5H2O in [bmim][PF6] ionic liquid (IL), with repeated recycling and reuse of the IL. [Copyright &y& Elsevier]

The reaction of racemic α-keto β-lactams 5a- 5c with the commercially available chiral compound trans-4-hydroxy- L-proline ( 6) in the presence of a catalytic amount of Bi(NO3)3⋅5 H2O in EtOH gave a diastereoisomer mixture of β-lactams with a pyrrole ring at C(3) ( 7 to 12). This is the first enantioselective synthesis of optically active β-lactams (=azetidin-2-ones) that possess a pyrrolyl residue at C(3), in a single step. [ABSTRACT FROM AUTHOR]