Chelated complexes of cadmium(II), cobalt(II), copper(II), mercury(II), nickel(II), uranyl(II) and zinc(II) with benzil bis(4-phenylthiosemicarbazone)

Summary Complexes of Co^II, Ni^II, Cu^II, Zn^II, Cd^II, Hg^II and UO ₂ ^II with benzil bis(4-phenylthiosemicarbazone), H₂BPT, have been synthesized and their structures assigned based on elemental analysis, molar conductivity, magnetic susceptibility and spectroscopic measurements. The i.r. spectra suggest that the ligand behaves as a binegative quadridentate (NSSN) (Co^II, Cu^II, Hg^II and UO ₂ ^II complexes) or as a binegative quadridentate-neutral bidentate chelating agent (Ni^II, Zn^II and Cd^II complexes). Octahedral structures for the Co^II and Ni^II complexes and square-planar structure for the Cu^II complex are suggested on the basis of magnetic and spectral evidence. The crystal field parameters (Dq, B and _B) for the Co^II complex are calculated and agree fairly well with the values reported for known octahedral complexes. The ligand can be used for the microdetermination of Ni^II ions of concentration in the 0.4–6×10^–4 mol l^–1 range and the apparent formation constant for the species generated in solution has also been calculated.     

Ultrasound assisted,VOSO4 catalyzed synthesis of 4-thiazolidinones: Antimicrobial evaluation of indazole-4-thiazolidinone derivatives

A simple and expedient multicomponent protocol was developed to synthesize 4-thiazolidinones by employing VOSO₄ as a catalyst under ultrasonic irradiation. The significant features of this protocol includes shorter reaction time, high yields, low catalyst loading, and also the catalyst can be recovered and reused up to next four cycles without significant loss in catalytic activity. All the synthesized novel indazole compounds were evaluated for their antibacterial and anti-biofilm activities. Compounds 9n, 9o and 9q showed promising activity (MIC value of 3.9?µg/mL) against K. planticola (MTCC 530). They also exhibited significant bactericidal activity against K. planticola (MTCC 530) (MBC value of 15.6?µg/mL). Additionally, 9n, 9o and 9q inhibited biofilm formation (IC₅₀ values ranging between 20.28–20.79?μg/mL) in this organism.     

Synthesis and biological screening of some chromonyl-substituted heterocycles derived from 2(3H)-furanone derivative

A 2(3H)-furanone bearing chromonyl moiety at position-3 was synthesized and utilized for the construction of N-heterocycles such as pyrrolone, N-aminoquinolone, and pyridazinone derivatives. The reactivity of the chromonylfuranone toward some nitrogen nucleophiles such as ammonia, benzylamine, hydrazine, and phenylhydrazine was studied. On the other hand, thiation of the starting chromonylfuranone interestingly provides mono- and di-thiated products. The chemoselectivity of these reactions is discussed. The structures of all products obtained were elucidated from their analytical and spectral data. The antimicrobial activities of selected examples of the synthesized compounds were examined against two strains of bacteria and two fungus strains. Some of them showed promising antimicrobial activities.     

Metal-free and azide-free synthesis of 1,2,3-triazoles derivatives

1,2,3-Triazoles, significant five-membered ring N-heterocycles, are main structural moieties in well-designed materials, pharmaceutical agents, bioactive products, and synthetic intermediates. In the research of life sciences and pharmaceuticals, by seeing the spacious applications of 1,2,3-triazoles, the progress of metal-free method is exceedingly desirable to evade the heterocyclic product metal contamination. Moreover, on a larger scale, the toxicity and explosiveness of azides makes azides discommode and hard to hold, to synthesize 1,2,3-triazoles. The need to steer the development of the synthesis of 1,2,3-triazoles toward more maintainable synthesis is a pressing issue. There are rare methods to construct 1,2,3-triazoles under azide-free and metal-free environments. These rare methods are compiled in this review. The afford of the collection and compilation of azide-free and metal-free synthesis methodologies of 1,2,3-triazole in single podium is supportive and crucial for synthetic chemist to extend the diversity of the synthesis of 1,2,3-trizoles through green protocol.     

Synthesis and structure determination of a new layered zincophosphate: [H2N2C6H16]0.5[Zn2(PO4)(HPO4)(H2O)]·H2O

The synthesis and crystal structure of a new microporous zincophosphate are described. [H₂N₂C₆H₁₆]_0.5[Zn₂(PO₄)(HPO₄)(H₂O)]·H₂O crystallizes in the triclinic space group P1¯ with a = 8.822(4), b = 9.236(4), c = 8.451(3) Å, = 67.19(3), = 91.32(3), = 111.10(3)°, V = 586.7(4) ų and Z = 2. This new material consists of infinite two-dimensional anionic layers alternated with planes containing organic diprotonated templates, N, N, N, N-tetramethylethylenediamine [H₂N₂C₆H₁₆]²⁺ molecules. The framework structure is built up of ZnO₄, ZnO₃OH₂, PO₄, and PO₃OH tetrahedra, linked through oxygen vertices. The presence of terminal OH₂ and OH groups, leads to an open structure containing four- and eight-rings. The organic molecules are interconnected to the framework through hydrogen bonds.     

Crystal and molecular structure of triphenylarsine

Triphenylarsine crystallizes in the triclinic space groupP¯1 (No. 2),a=11.200(2),b=15.263(7),c=17.871(6) Å,=84.63(5),=80.21(5), =86.41(6)°,Z=8, with four molecules in the asymmetric unit. The structure was solved by direct methods and refined in the initial stages by full-matrix least squares and finally by block-diagonal least-squares methods toR=0.055 for 3537 reflections. The dimensions and the conformations of the four independent molecules are almost identical. The molecules do not exhibitC _3v symmetry.     

1H-1,2,3-triazole,a promising precursor for chemical vapor deposition of hydrogenated carbon nitride

Well-crystallized hydrogenated carbon nitride thin films have been prepared by microwave plasma enhanced chemical vapor deposition (MWPECVD). 1H-1,2,3-triazole+N₂ and Si (1 0 0) were used as precursor and substrate, respectively. Substrate temperature during the deposition was recorded to be 850 °C. The synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photo-electron spectroscopy (XPS) analyses. The plasma compositions were checked by optical emission spectroscopy (OES). XRD observation strongly suggests that the films contain polycrystalline carbon nitride with graphitic structure of (1 0 0), (0 0 2), (2 0 0) and (0 0 4). XPS peak quantification reveals that the atomic ratio of the materials C:N:O:Si is 32:41:18:9. X-ray photo-electron peak deconvolution shows that the most dominant peak of C (1s) and N (1s) narrow scans correspond to sp² hybrid structure of C₃N₄. These observations indicate that 1H-1,2,3-triazole favors the formation of hydrogenated carbon nitride with graphitic phase by CVD method and thus is in good agreement with XRD results. SEM of surface and OES of plasma also support the formation of polycrystalline carbon nitride films from 1H-1,2,3-triazole+N₂ by CVD.     

Synthesis and crystal structure of bis(4-methylpiperidine-dithiocarbamato-S,S′)-palladium(II)

The complex bis(4-methylpiperidine-dithiocarbamato-S,S′)-palladium(II) was synthesized by the reaction of 4-methyl-1-piperidine dithiocarbamic acid with palladium(II) chloride. Its structure was determined by X-ray crystal diffraction analysis. It crystallizes in the monoclinic P2₁/c space group with the crystal cell parameters a=8.6491(8) ?, b=18.7305(16) ?, c=11.9933(10) ?, β=107.074(1)°, V=1857.3(3) ?³ and Z=4. The palladium (II) ion is bonded to four sulfur atoms, belonging to two dithiocarbamate ligands, in a distorted square planar geometry. The X-ray data suggest a pronounced electronic delocalization in the two NCS₂ moieties.