NOPR Collection:

Synthesis of 4-{(E)-[(3-methyl-5-sulphanyl-4H-1,2,4-triazol-4-yl)imino]methyl} benzaldehyde and its complexes with Ag(I), Hg(II), Zn(II), Co(II), Ni(II) ions and its characterisation

2021-06-15T09:12:29Z

Title: Synthesis of 4-{(E)-[(3-methyl-5-sulphanyl-4H-1,2,4-triazol-4-yl)imino]methyl} benzaldehyde and its complexes with Ag(I), Hg(II), Zn(II), Co(II), Ni(II) ions and its characterisation Authors: Ashwini; Bhat, Gopalakrishna N; Nazareth, Ronald A Abstract: A novel Schiff base 4-{(E)-[(3-methyl-5-sulphanyl-4H-1,2,4-triazol-4-yl)imino]methyl}benzaldehyde (MSTB) and its complexes with Ag(I), Hg(II), Cu(II), Ni(II) and Co(II) have been prepared. MSTB is prepared by the condensation reaction between triazole and terephthaldehyde. In complexes, MSTB molecules are found to link with the metal ion, through thiolsulphur after deprotonation and the nitrogen of the azomethine group. The composition of the complexes are found to be ML where M =Ag, ML₂ where M=Zn, Hg and ML₂(H₂O)₂ where M= Co, Ni. Linear polymeric structure is proposed for Ag(I) complex, tetrahedral structure is proposed for Zn(II) and Hg(II) complexes and octahedral structure is proposed for Co(II) and Ni(II) complexes. Page(s): 649-655

Mo- and W-containing layered double hydroxides: Mild and selective oxidation of alkenes with H2O2

2021-06-15T09:10:01Z

Title: Mo- and W-containing layered double hydroxides: Mild and selective oxidation of alkenes with H2O2 Authors: Agarwalla, Uday Sankar Abstract: Molybdenum- and tungsten-containing (M₇O₂₄^6-, M = Mo or W) layered double hydroxides (LDHs) with Mg²⁺ and Al³⁺ cations in the brucite-like layer have been prepared by direct anion exchange, starting from the corresponding terephthalate precursor. The solids have been characterized by various instrumental techniques such as elemental chemical analysis, powder X-ray diffraction, infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and thermogravimetric analysis. The M₇O₂₄^6-intercalated LDHs have been explored as catalysts for the selective oxidation of a series of alkenes at room temperature using safer, inexpensive and environmentally benign hydrogen peroxide as oxidant. Reaction conditions have been optimized considering different reaction parameters to achieve maximum conversion in the catalytic oxidation reaction. Recycling of the catalyst has shown that it can be reused up to three more cycles without significant loss of performance. Page(s): 656-662

Synthesis, structure and molecular Hirshfeld surface analysis of polymeric cadmium(II) complex involving tetradentate N3S-donor ligand and dicyanamide as bridging ligand

2021-06-15T08:59:50Z

Title: Synthesis, structure and molecular Hirshfeld surface analysis of polymeric cadmium(II) complex involving tetradentate N3S-donor ligand and dicyanamide as bridging ligand Authors: Munshi, Sadeka J; Sadhu, Mehul H; Guin, Mridula; Kumar, Sujit B Abstract: One new polymeric cadmium(II) complex {[Cd(bdmpe)(µ_1,5-dca)]ClO₄.CH₃OH}_nhas been synthesized by the reaction of cadmium perchlorate with ligand N,N-bis((3,5-dimethyl-1H-pyrazol-1-yl)methyl)-2-(phenylthio)ethan-1-amine (bdmpe) in presence of dca (dicyanamide, N(CN)₂^-) as bridging ligand in methanol and characterized by spectroscopic techniques. Single crystal X-ray diffraction study of the complex confirmed that it has polymeric 1D chain and each cadmium centre has distorted octahedral geometry with N₅S coordination and is bonded through two terminal nitrile group of the dca ligand using m_1,5 coordination modes. Intermolecular interactions and packing modes of the compound are described by Hirshfeld surface analysis and two dimensional finger print plots. Page(s): 663-668

Synthesis, crystal structure, thermal analysis and molecular interactions of bis(3,5-dimethyl-3H-1,2,4-triazole)octamolybdate

2021-06-15T08:51:02Z

Title: Synthesis, crystal structure, thermal analysis and molecular interactions of bis(3,5-dimethyl-3H-1,2,4-triazole)octamolybdate Authors: Reddy, K Hussain; Phanimala, C; Krishna, P Murali; Kumar, G N Anil Abstract: This paper describes the synthesis of {bis(3,5-dimethyl-3H-1,2,4-triazole)octamolybdate}(2:1) molecule by mixing bis(acetylacetonato)dioxo molybdenum(VI) and 3-(E)-{1-(furan-2-yl)ethylidene)amino]-1-phenylurea. The structure of the molecule was determined by using single crystal X-ray diffraction technique. Structure determination reveals that the title complex Mo₈O₂₆.2(C₄H₉N₃) contains two moieties namely an octamolybdate [Mo₈O₂₆] complex, and 3,5-dimethyl-1,2,4-triazole [2(C₄H₉N₃)] in the unit cell. The [Mo₈O₂₆] unit consists of two {Mo₄O₁₃} subunits linked together by bridging oxygen atoms with an approximate C_2h symmetry under Triclinic system, P space group with lattice parameters a = 10.1007(2), b = 10.3887(2), c = 13.0380(3) Å, α = 66.921(3) β = 69.466(3) γ = 62.892(2)°. The octamolybdate units are linked by methylmethanamine as chains via N-H…O interactions. The ¹H-¹H COSY NMR recorded in DMSO-d₆ spectral data indicates the absence of the coupling between the protons. The thermal analysis indicates that the complex is thermally stable. The Hirshfeld surface of the compound mapped with d_norm (-1.0 a.u. to 1.0 a.u.) and the deep red spot on the Hirshfeld surface depicts the formation of strong N-H···O hydrogen bond. Page(s): 669-675