Promising CO2 Capture and Effective Iodine Adsorption of Hyper-Cross-Linked Conjugated Porous Organic Polymers Prepared from a Cyclopentannulation Reaction.

Three novel conjugated porous organic polymers, denoted as C-POP1-3 and which consist of alternating pyrene cores with various contorted fluorene surrogates, were successfully synthesized from a versatile one-pot palladium-catalyzed [3+2] cyclocondensation reaction. The resulting polymers were obtained in excellent yields and displayed weight-average molecular weights (Mw) ranging from 12.2 to 20.2 kg/mol with polydispersity indices (Mw/Mn) ranging between 1.8 and 2.4, suggesting that the molecular masses are narrowly distributed and thus implying homogeneous polymer chains. Thermal stability exploration of C-POP1-3 by thermogravimetric analysis (TGA) revealed an impressive robustness with a 10% weight reduction temperature attaining 485 °C. Investigation of the inherent microporosity properties of C-POP1-3 via nitrogen adsorption experiments using Brunauer-Emmett-Teller (BET) theory discloses their surface areas which reach up to 560 m2 g-1 and pore volumes averaging 0.47 cm3 g-1. The target conjugated polymers were explored as adsorbents disclosing a maximum carbon dioxide adsorption of 83.0 mg g-1 at 273 K and low pressure for C-POP1, whereas iodine sorption tests portrayed prominent outcomes, notably for C-POP3 which proved to owe a strong affinity toward the hitherto mentioned halogen by achieving a maximum adsorption of 2220 mg g-1. Additionally, recyclability experiments confirmed the possibility to regenerate the polymers' adsorption capabilities even after seven consecutive cycles of adsorption-desorption cycles, which qualify them as auspicious iodine adsorbents.

Tröger's Base-Enriched Conjugated Cyclopentannulated Copolymers: Prominent Adsorbents of CO2, H2, and Iodine.

Three copolymers with conjugated structures, PTB1-PTB3, were produced utilizing a palladium-catalyzed cyclopentannulation polymerization by reacting a specially designed diethynyl Tröger's base surrogate with different dihalogenated polycondensed aromatic hydrocarbons. Brunauer, Emmet, and Teller nitrogen gas adsorption investigation revealed the surface areas of the copolymers, attaining ∼365 m2 g-1. Gas uptake studies demonstrated a considerable carbon dioxide uptake for PTB2 of 44.41 mg g-1 at 273 K and a promising H2 gas uptake of 3.18 mg g-1 at 77 K. PTB1-PTB3 displayed a sizable iodine adsorption capacity, achieving 4000 mg g-1, and mechanistic investigations demonstrated the prevalence of a pseudo-second-order kinetic model. Recyclability experiments proved the effective regeneration of the copolymers, even after performing several adsorption and desorption tests.

Efficient Iodine Uptake of Ultra Thermally Stable Conjugated Copolymers Bearing Biaceanthrylenyl Moieties and Contorted Aromatic Units Using a [3 + 2] Palladium-Catalyzed Cyclopolymerization Reaction.

A novel series of copolymers made from alternating aromatic surrogates with contorted and spiro compounds, denoted as BCP1-3, was successfully synthesized employing a palladium-catalyzed one-pot [3 + 2] cyclopentannulation reaction. The resulting copolymers BCP1-3, which were isolated in high yields, exhibited weight-average molecular weights (Mw) ranging from 11.0 to 61.5 kg mol-1 (kDa) and polydispersity index (Mw/Mn) values in the range of 1.7 and 2.0, which suggest a narrow molecular weight distribution, thus indicating the formation of uniform copolymer chains. Investigation of the thermal properties of BCP1-3 by thermogravimetric analysis disclosed outstanding stability with 10% weight loss temperature values reaching 800 °C. Iodine adsorption tests revealed remarkable results, particularly for BCP2, which demonstrated a strong affinity toward iodine reaching an uptake of 2900 mg g-1. Additionally, recyclability tests showcased the effective regeneration of BCP2 after several successive iodine adsorption-desorption cycles.

Iodine and Nickel Ions Adsorption by Conjugated Copolymers Bearing Repeating Units of Dicyclopentapyrenyl and Various Thiophene Derivatives.

The synthesis of three conjugated copolymers TPP1-3 was carried out using a palladium-catalyzed [3+2] cycloaddition polymerization of 1,6-dibromopyrene with various dialkynyl thiophene derivatives 3a-c. The target copolymers were obtained in excellent yields and high purity, as confirmed by instrumental analyses. TPP1-3 were found to divulge a conspicuous iodine adsorption capacity up to 3900 mg g-1, whereas the adsorption mechanism studies revealed a pseudo-second-order kinetic model. Furthermore, recyclability tests of TPP3, the copolymer which revealed the maximum iodine uptake, disclosed its efficient regeneration even after numerous adsorption-desorption cycles. Interestingly, the target copolymers proved promising nickel ions capture efficiencies from water with a maximum equilibrium adsorption capacity (qe) of 48.5 mg g-1.

Efficient Removal of Carcinogenic Azo Dyes from Water Using Iron(II) Clathrochelate Derived Metalorganic Copolymers Made from a Copper-Catalyzed [4 + 2] Cyclobenzannulation Reaction.

A novel synthetic strategy is disclosed to prepare a new class of metalorganic copolymers that contain iron(II) clathrochelate building blocks by employing a mild and cost-effective copper-catalyzed [4 + 2] cyclobenzannulation reaction, using three specially designed diethynyl iron(II) clathrochelate synthons. The target copolymers CBP1-3 were isolated in high purity and excellent yields as proven by their structural and photophysical characterization, namely, Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and UV-VIS absorption and emission spectroscopies. The thermogravimetric analysis (TGA) of CBP1-3 revealed an excellent chemical stability. Investigation of the adsorption properties of the target copolymers towards the carcinogenic methyl red dye from aqueous solution revealed a quantitative uptake in 30 min. Isothermal adsorption studies disclosed that methyl red uptake from aqueous solution followed the Langmuir model for all of the target copolymers, reaching a maximum adsorption capacity (qm) of 431 mg g-. Kinetic investigation revealed that the adsorption followed pseudo-first-order with an equilibrium adsorption capacity (qe,cal) of 79.35 mg g- and whose sorption property was sustained even after its reuse several times.

High Uptake of the Carcinogenic Pararosaniline Hydrochloride Dye from Water Using Carbazole-Containing Conjugated Copolymers Synthesized from a One-Pot Cyclopentannulation Reaction.

Three conjugated copolymers CAP1-3 were synthesized in one-step via a typical [3+2] cyclopentannulation reaction using a specially designed diethynyl carbazole synthon with various dibrominated polycondensed aromatic hydrocarbons (PAHs). The desired copolymers CAP1-3 were obtained in excellent yields, and their structures were confirmed by 1H- and 13C- nuclear magnetic spectroscopy (NMR), whereas gel permeation chromatography revealed weight-average molar masses (Mw) up to 19.9 kDa with a polydispersity index (PDI) in the range of 2.2-2.6. Interestingly, CAP1-3 exhibits an outstanding capacity to adsorb the carcinogenic pararosaniline hydrochloride dye (Basic Red 9, BR9) from aqueous solutions. Isothermal adsorption studies were carried out following the linear models of Langmuir and Freundlich, divulging an adsorption capacity maximum (qm) toward BR9 of 483.09 mg g-1. Investigation of the dye uptake mechanism on CAP1-3 revealed a pseudo-second-order kinetic model for the target copolymer that showed the highest uptake capacity. Recyclability tests disclosed an excellent adsorption efficiency of BR 9 reaching 93% after six cycles.

Aggregation-Induced Emission of Contorted Polycondensed Aromatic Hydrocarbons Made by Edge Extension Using a Palladium-Catalyzed Cyclopentannulation Reaction.

Contorted polycyclic aromatic hydrocarbons (PAHs), CPA1-2 and CPB1-2, bearing peripheral five-membered rings were synthesized employing a palladium-catalyzed cyclopentannulation reaction using specially designed diaryl acetylene synthons TPE and TPEN with commercially available dibromo- anthracene DBA and bianthracene DBBA derivatives. The resulting target compounds CPA1-2 and CPB1-2 were isolated in excellent yield and found to be highly soluble in common organic solvents, which allowed for their structural characterization and investigation of the photophysical properties, disclosing their aggregation-induced emission (AIE) properties in THF at selective concentration ranges of water fractions in the solvent mixture. Examination of the contorted PAH structures by means of density functional theory (DFT) revealed higher electronic conjugation in the more rigid and planar anthracene-containing CPA1-2 derivatives when compared to the twisted bianthracene-bearing moieties CBPA1-2 with HOMO-LUMO bandgaps (ΔE) of ∼2.32 eV for the former PAHs and ∼2.78 eV for the latter ones.

Synthesis and Iodine Adsorption Properties of Organometallic Copolymers with Propeller-Shaped Fe(II) Clathrochelates Bridged by Different Diaryl Thioether and Their Oxidized Sulfone Derivatives.

Three organometallic copolymers, ICP1-3, containing iron(II) clathrochelate units with cyclohexyl lateral groups and interconnected by various thioether derivatives were synthesized. The reaction of the latter into their corresponding OICP1-3 sulfone derivatives was achieved quantitatively using mild oxidation reaction conditions. The target copolymers, ICP1-3 and OICP1-3, were characterized by various instrumental analysis techniques, and their iodine uptake studies disclosed excellent iodine properties, reaching a maximum of 360 wt.% (qe = 3600 mg g-1). The adsorption mechanisms of the copolymers were explored using pseudo-first-order and pseudo-second-order kinetic models. Furthermore, regeneration tests confirmed the efficiency of the target copolymers for their iodine adsorption even after several adsorption-desorption cycles.

Synthesis of Iron(II) Clathrochelate-Based Poly(vinylene sulfide) with Tetraphenylbenzene Bridging Units and Their Selective Oxidation into Their Corresponding Poly(vinylene sulfone) Copolymers: Promising Materials for Iodine Capture.

The development of a simple and efficient synthetic methodology to engineer functional polymer materials for gas adsorption is necessary due to its relevance for various applications. Herein, we report the synthesis of metalorganic poly(vinylene sulfide) copolymers CTP1-3 with iron(II) clathrochelate of various side groups connected by tetraphenylbenzene units. CTP1-3 were subsequently oxidized into their respective poly(vinylene sulfone) copolymers CTP4-6 under green reaction conditions. The target copolymers CTP1-6 were characterized using various instrumental analysis techniques. Examination of the iodine adsorption properties of the copolymers revealed high iodine uptake properties, reaching 2360 mg g-1 for CTP2, and whose reusability tests proved its efficient regeneration, thus proving the importance of iron(II) clathrochelate polymers in iodine capture.

Synthesis of Metalorganic Copolymers Containing Various Contorted Units and Iron(II) Clathrochelates with Lateral Butyl Chains: Conspicuous Adsorbents of Lithium Ions and Methylene Blue.

We report the synthesis of three highly soluble metalorganic copolymers, TCP1-3, that were made from a one-pot complexation of iron(II) clathrochelate units that are interconnected by various thioether-containing contorted groups. TCP1-3 were converted into their poly(vinyl sulfone) derivatives OTCP1-3 quantitatively via the selective oxidation of the thioether moieties into their respective sulfones. All of the copolymers, TCP1-3 and OTCP1-3, underwent structural analysis by various techniques; namely, 1H- and 13C-nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and gel permeation chromatography (GPC). The copolymers were tested as potent lithium ions adsorbents revealing a maximum adsorption (qm) value of 2.31 mg g-1 for OTCP2. Furthermore, this same copolymer was found to be a promising adsorbent of methylene blue (MEB); an isothermal adsorption study divulged that OTCP2's uptake of MEB from an aqueous solution (following the Langmuir model) was, at maximum adsorption capacity, (qm) of 480.77 mg g-1; whereas the kinetic study divulged that the adsorption follows pseudo second-order kinetics with an equilibrium adsorption capacity (qe,cal) of 45.40 mg g-1.

Highly Selective and Sensitive Aggregation-Induced Emission of Fluorescein-Coated Metal Oxide Nanoparticles.

We report the synthesis, characterization, and photophysical properties of novel metal oxide nanoparticles (NPs) coated with specially designed fluorescein substituents which are capped with electron-withdrawing groups. The fluorescein-coated nanoparticles were synthesized in excellent yields, and their structures were confirmed using various advanced spectroscopic, instrumental, and surface analysis techniques, revealing the formation of the target functionalized nanoparticles (FNPs) which show superior chemical and thermal stabilities. In addition, the photophysical properties of the FNPs were examined using UV-visible absorption and fluorescence spectroscopy. These latter techniques disclosed aggregation-induced emission (AIE) properties for most of the target FNPs, namely those which are soluble in common organic solvents at selective concentration ranges of water fractions in the solvent mixture.

Fluorinated Iron(ii) clathrochelate units in metalorganic based copolymers: improved porosity, iodine uptake, and dye adsorption properties.

We report the synthesis of metalorganic copolymers made from the palladium catalyzed Sonogashira cross-coupling reaction between various iron(ii) clathrochelate building blocks with diethynyl-triptycene and fluorene derivatives. The target copolymers CCP1-5 were isolated in excellent yield and characterized by various instrumental analysis techniques. Interestingly, investigation of the copolymers' porosity properties discloses BET surface areas up to 337 m2 g-1 for the target compounds bearing fluorinated iron(ii) clathrochelate units CCP2,5. Moreover, the fluorinated copolymers display an outstanding uptake capacity of iodine with a maximum adsorption of 200 wt%. The target metalorganic copolymers CCP1-5 reveal very good adsorption of organic dyes, namely, methyl blue and methylene blue, from aqueous media.

Selective removal of toxic organic dyes using TrÓ§ger base-containing sulfone copolymers made from a metal-free thiol-yne click reaction followed by oxidation.

Three copolymers TCP1-3 bearing TrÓ§ger's base (TB) units intercalated with various thioether groups were synthesized using a catalyst-free thiol-yne click reaction. TCP1-3 display excellent solubility in common organic solvents allowing for their structural, and photophysical characterization. The thioether groups in TCP1-3 were selectively oxidized into their respective sulfone derivatives under mild oxidation reaction conditions affording the postmodified copolymers TCP4-6. Investigation of organic dye uptake from water by TCP1-6 proved their efficiency as selective adsorbents removing up to 100% of the cationic dye methylene blue (MEB) when compared to anionic dyes, such as Congo red (CR), methyl orange (MO) and methyl blue (MB). The sulfone-containing copolymers TCP4-6 display superior and faster MEB removal efficiencies with respect to their corresponding synthons TCP1-3.

Synthesis, evaluation and molecular docking studies of amino acid derived N-glycoconjugates as antibacterial agents.

Six amino acid derived N-glycoconjugates of d-glucose were synthesized, characterized and tested for antibacterial activity against G(+)ve (Bacillus cereus) as well as G(-)ve (Escherichia coli and Klebsiella pneumoniae) bacterial strains. All the tested compounds exhibited moderate to good antibacterial activity against these bacterial strains. The results were compared with the antibacterial activity of standard drug Chloramphenicol, where results of A5 (Tryptophan derived glycoconjugates) against E. coli and A4 (Isoleucine derived glycoconjugates) against K. pneumoniae bacterial strains are comparable with the standard drug molecule. In silico docking studies were also performed in order to understand the mode of action and binding interactions of these molecules. The docking studies revealed that, occupation of compound A5 at the ATP binding site of subunit GyrB (DNA gyrase, PDB ID: 3TTZ) via hydrophobic and hydrogen bonding interactions may be the reason for its significant in vitro antibacterial activity.