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This work describes a new well-defined, air-stable, phosphine free palladium(II) [Pd(L)Cl] (1) catalyst. This catalyst was utilized for N-alkylation of amines and indole synthesis where H2O was found to be the by-product. A broad range of aromatic amines were alkylated using this homogeneous catalyst with a catalyst loading of 0.1 mol%. Greener aromatic and aliphatic primary alcohols were utilized and a hydrogen auto-transfer strategy via a metal–ligand cooperative approach was investigated. The precursor of the antihistamine-containing drug molecule tripelennamine was synthesized on a gram scale for large-scale applicability of the current synthetic methodology. A number of control experiments were performed to investigate the possible reaction pathway and the outcomes of these experiments indicated the azo-chromophore as a hydrogen reservoir during the catalytic cycle. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis of flavone, quinolone, and benzofuran derivatives, which have diverse pharmacological applications. The authors introduce a new synthetic methodology using designed transition-metal complexes. The study focuses on the cyclization of 2'-hydroxychalcones using different transition-metal catalysts and explores the effects of different substituents on the phenyl rings. The article also discusses the synthesis and characterization of catalysts and provides information on the synthesis and characterization of various compounds, including 2-phenylquinolin-4(1H)-ones and benzofurochromenone compounds. The compounds were synthesized, characterized, and analyzed using various spectroscopic techniques. The document also mentions the detection of hydrogen peroxide during the catalytic reactions and acknowledges the funding and support received for the research. [Extracted from the article]

In the present work, mononuclear copper(II) complexes [Cu(L1)Cl](1) and [Cu(L2)Cl](2) having meridional tridentate "NNO" ligands with different substituents have been synthesized and the complexes were characterized by different analytical and spectral techniques, namely FT-IR, NMR, and UV-Vis spectral studies. Molecular structures of complexes 1 and 2 were determined by single-crystal X-ray crystallography. These complexes have been utilized as a catalyst for the synthesis of substituted benzoxazole derivatives under mild conditions. A total of 34 benzoxazole derivatives having different substituents were prepared. The mechanism of this multicomponent reaction, catalysed by complexes 1 and 2, was investigated and the proposed reaction mechanism was based on H-atom abstraction by the phenoxyl radical complex. [ABSTRACT FROM AUTHOR]

In this work, cobalt complexes 1 and 2 were synthesized from ligands L1 (1,2-bis(2-phenyl-2-(pyridin-2-yl)hydrazineylidene)ethane) and L2 (1,2-bis(2-(pyridin-2-yl)hydrazineylidene)ethane) in moderate yields. These complexes were characterized by UV-visible, IR and ESI-MS spectroscopic studies. The molecular structure of complex 1 was determined by X-ray crystallography. Complexes 1 and 2 were employed as catalysts for the oxidation of sp3 C–H bonds. A total of 12 substrates were investigated for the oxidation of benzylic and aliphatic sp3 C–H bonds. A reaction pathway was proposed and possible reactive intermediate species was successfully characterized by ESI-MS spectroscopic studies. [ABSTRACT FROM AUTHOR]

The chemotherapeutic potential of ruthenium(II) complexes has recently attracted researchers' interest as antibacterial and anticancer agents. In this study, two novel half-sandwich imine-based Ru complexes ([Ru(p-cymene)Cl(L-1)][PF6] (Ru-1) and [Ru(p-cymene)Cl(L-2)][PF6] (Ru-2)) were reported for their deoxyribonucleic acid (DNA) binding and antitubercular, antibacterial, and anticancer activities. The molecular structure of Ru-2 was obtained by single-crystal X-ray crystallography. DNA interaction studies were conducted by UV-Vis absorbance and fluorescence spectral titration which gave rise to DNA binding constants (Kb) of 1.32 × 106 and 1.82 × 106 for Ru-1 and Ru-2, respectively and the Stern–Volmer binding constant (KSV) values for Ru-1 and Ru-2 were 1.7763 × 104 M−1 and 7.6 × 103 M−1, respectively. The in vitro antitubercular activity was evaluated against Mycobacterium tuberculosis H37Ra. The antibacterial potential of both the Ru-complexes was examined against Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus and Bacillus subtilis) bacteria. The half-maximal inhibitory concentration (IC50) values for the antitubercular activity of Ru-1 and Ru-2 were 4.87 ± 1.32 μM and 5.78 ± 0.54 μM, respectively. A cytotoxic study of these complexes was performed against the human breast cancer cell line (MCF-7) and the human embryonic kidney cell line (HEK293) (normal cells). The study revealed meaningful activity of the Ru-1 complex against (cancer) MCF-7 cells, while the viability of HEK293 (normal) cells in the presence of Ru-2 was higher as compared to a reference drug 5FU. We suggest that these kinds of Ru-complexes could have potential for application in metallopharmaceuticals. [ABSTRACT FROM AUTHOR]

A series of new unsymmetrical (XYC–1 type) palladacycles (C1–C4) were designed and synthesized with simple anchoring ligands L1–4H (L1H = 2‐((2‐(4‐methoxybenzylidene)‐1‐phenylhydrazinyl)methyl)pyridine, L2H = N,N‐dimethyl‐4‐((2‐phenyl‐2‐(pyridin‐2‐ylmethyl)hydrazono)methyl)aniline, L3H = N,N‐diethyl‐4‐((2‐phenyl‐2‐(pyridin‐2‐ylmethyl)hydrazono)methyl) aniline and L4H = 4‐(4‐((2‐phenyl‐2‐(pyridin‐2‐ylmethyl)hydrazono) methyl)phenyl)morpholine H = dissociable proton). Molecular structure of catalysts (C1–C4) were further established by single X‐ray crystallographic studies. The catalytic performance of palladacycles (C1–C4) was explored with the direct Csp2–H arylation of imidazoles with aryl halide derivatives. These palladacycles were also applied for investigating of Mizoroki–Heck reactions with aryl halides and acrylate derivatives. During catalytic cycle in situ generated Pd(0) nanoparticles were characterized by XPS, SEM and TEM analysis and possible reaction pathways were proposed. The catalyst was employed as a pre‐catalyst for the gram‐scale synthesis of octinoxate, which is utilized as a UV‐B sunscreen agent. [ABSTRACT FROM AUTHOR]

This work describes a new well-defined, air-stable, phosphine free palladium(II) [Pd(L)Cl] (1) catalyst. This catalyst was utilized for N -alkylation of amines and indole synthesis where H 2 O was found to be the by-product. A broad range of aromatic amines were alkylated using this homogeneous catalyst with a catalyst loading of 0.1 mol%. Greener aromatic and aliphatic primary alcohols were utilized and a hydrogen auto-transfer strategy via a metal-ligand cooperative approach was investigated. The precursor of the antihistamine-containing drug molecule tripelennamine was synthesized on a gram scale for large-scale applicability of the current synthetic methodology. A number of control experiments were performed to investigate the possible reaction pathway and the outcomes of these experiments indicated the azo-chromophore as a hydrogen reservoir during the catalytic cycle.

Ligands derived from 2-(1-phenylhydrazinyl)pyridine and salicylaldehyde (HL 1 ), 3-methoxysalicylaldehyde (HL 2 ), 5-bromosalicylaldehyde (HL 3 ), and 3,5-di- tert -butylsalicylaldehyde (HL 4 ) react with [V IV O(acac) 2 ] in MeOH followed by aerial oxidation to give [V V O 2 (L 1 )] ( 1 ), [V V O 2 (L 2 )] ( 2 ), [V V O 2 (L 3 )] ( 3 ), and [V V O 2 (L 4 )] ( 4 ). Complex [V IV O(acac)(L 1 )] ( 5 ) is also isolable from [V IV O(acac) 2 ] and HL 1 in dry MeOH. Structures of all complexes were confirmed by single-crystal X-ray and spectroscopic studies. They efficiently catalyze benzyl alcohol and its derivatives' oxidation in the presence of H 2 O 2 to their corresponding aldehydes. Under optimized reaction conditions using 1 as a catalyst precursor, conversion of benzyl alcohol follows the order: 4 (93%) > 2 (90%) > 1 (86%) > 3 (84%) ≈ 5 (84%). These complexes were also evaluated for antifungal and antiproliferative activities. Complex 3 with MIC 50 = 16 μg/mL, 4 with MIC 50 = 12 μg/mL, and 5 with MIC 50 = 16 μg/mL are efficient toward planktonic cells of Candida albicans and Candida tropicalis . On Michigan cancer foundation-7 (MCF-7) cells, they show comparable cytotoxic effects and exhibit IC 50 in the 27.3-33.5 μg/mL range, and among these, 4 exhibits the highest cytotoxicity. A similar study on human embryonic kidney cells (HEK293) confirms their less toxicity at lower concentrations (4 to 16 μg/mL) compared to MCF-7.

An efficient dual functional naphthalene-derived Schiff base NpSb probe has been synthesised and evaluated for its fluorescence and chromogenic response towards metal ions. The NpSb probe was capable of selectively recognising Al 3+ and Zn 2+ ions when they were excited at the same wavelength in an aqueous organic solvent system. Almost non-fluorescent NpSb displayed a 'turn-on' fluorescence response when treated with Zn 2+ ( λ em = 416 nm) and Al 3+ ( λ em = 469 nm) ions due to the chelation-enhanced fluorescence (CHEF) effect. The limit of detection (LoD) values for Al 3+ and Zn 2+ have been determined to be 38.0 nM and 43.0 nM, respectively. The binding constants for Al 3+ and Zn 2+ were found to be 1.18 × 10 6 M -1 and 3.5 × 10 5 M -1 , respectively. The NpSb also acted as a colorimetric sensor for Al 3+ as the colour of the probe's solution turned to pale green from colourless upon Al 3+ addition. The binding mechanism between NpSb and Zn 2+ /Al 3+ was supported by the ESI-MS, Job's plot, NMR, and DFT studies. The reversibility experiments were carried out with an F - ion and EDTA with the development of corresponding logic gates. Moreover, NpSb could be applied to detect Al 3+ ions in real samples such as tap water, distilled water and soil samples.