查看更多>>摘要：Y Bis[(2-diphenylphosphino)phenyl] ether (DPEphos) was used as chelating ligand to prepare the corresponding borohydride complex [Cu(kappa(2)-BH4)(DPEphos)], whose structure was ascertained spectroscopically and by means of X-ray diffraction. The spectroscopic assignments related to the coordinated borohydride were confirmed by preparing the isotopologue [Cu(kappa(2) -BD4)(DPEphos)]. Reaction of [Cu(kappa(2)-BH4)(DPEphos)] with triflic acid afforded the dimer [Cu-2(mu-BH4)(DPEphos)(2)][OTf] (OTf = triflate). The borohydride complexes exhibited appreciable blue emission upon excitation with UV light at room temperature. [Cu(kappa(2)-BH4)(DPEphos)] revealed to be a suitable precursor for the preparation of luminescent heteroleptic copper(I) complexes having general formula [Cu(N<^>N)(DPEphos)]+ (N<^>N = 1,10-phenantroline, 2,9-dimethyl-1,10-phenantroline, 2,2'-bypiridine, 4,4'-dimethyl-2,2'bipyridine). (C) 2021 Elsevier B.V. All rights reserved.
查看更多>>摘要：Y Traditional microporous SAPO-11 molecular sieve was synthesized in Al2O3-P2O5 -Dipropylamine-H2O system. To improve the mesoporosity aiming to overcome the diffusion limitations of zeolite, Hierarchical mesoporous SAPO-11 molecular sieve was synthesized via adding SAPO-11 seed into the Al2O3-P2O5-Dipropylamine-H2O system. Nitrogen physisorption analysis indicated that the synthesized SAPO-11 via seeding approach has additional mesoporosity with a mesopore volume of 0.11 cm(3)/g and average pore diameter similar to 4 nm. Also, HR-TEM analysis proofed the formation of hierarchical mesoporous SAPO-11 as spherical aggregate particles in contrast to rectangular block crystals in the form of large particle aggregates showed by traditional micro-SAPO-11. To investigate the effect of the created mesoporosity on the catalytic performance toward n-heptane hydroisomerization, Hierarchical mesoporous SAPO-11-support was employed to prepare PtSn (x) bimetallic bifunctional catalysts. Compared to PtSn(2)/micro-SAPO-11 catalyst, the PtSn(2)/meso-SAPO-11 catalyst exhibited higher isomerization selectivity, attributed to their excellent diffusion properties resulting from the hierarchical pore network, which is beneficial for catalytic reactions. (C) 2021 Elsevier B.V. All rights reserved.
查看更多>>摘要：Halide-bridged metal precursors [(arene)MCl2](2) (arene = p-cymene, Cp*; M = Ru, Rh and Ir) on reaction with thiosemicarbazone derivative ligands (L1, L2 and L3) yielded a series of mononuclear ruthenium, rhodium and iridium complexes and their corresponding dinuclear analogues. All these complexes (1-9) were characterized by analytical and spectroscopic techniques. Single-crystal X-ray diffraction studies determined the molecular structures of complexes 1, 5, 7-9. The compounds were screened for their in vitro antibacterial activity against gram-positive Staphylococcus aureus (MTCC 3160, MMSA, ESKAPE) and Bacillus thuringiensis (MTCC 8995) and gram-negative Escherichia coli (MTCC 1687) and Pseudomonas aeruginosa (MTCC 1688, ESKAPE) strains, where they exhibit the significant antibacterial effect. In addition, the compounds were also investigated for antioxidant activities using DPPH radical scavenging assays, in which most of them displayed substantial antioxidant activities. Furthermore, the binding of ligand L3 with biomolecules such as Salmon milt DNA (SM-DNA) investigated by UV-Vis absorption spectroscopy revealed an intercalative mode of interaction. (C) 2021 Elsevier B.V. All rights reserved.
Volkov, M. A.Fedoseev, A. M.Krivoborodov, E. G.Toropygin, I. Y....
7页
查看更多>>摘要：Acetates of actinides and their fission products were essential for the development of radiochemical industries using acetate precipitation technology. Despite this, the literature describes only the synthesis of species containing technetium in the oxidation state + 3 and higher. New synthetic routes for the preparation of technetium + 2.5 carboxylate polymer clusters using readily available technetium (IV) oxide as a precursor are developed in the present study. The crystal structure of synthesized complexes is studied by X-ray diffraction analysis (XRD) at different temperatures, and the coefficients of thermal expansion along the axes of the crystal lattice and in the direction of the polymer chain growth are determined. Matrix assisted laser desorption/ionization-time of flight (MALDI-ToF) mass-spectrometry showed stability of technetium carboxylates under conditions of laser ionization, which allows suggesting the possibility of technetium coatings deposition from the gas phase. Based on the obtained experimental results a reaction mechanism for the formation of tetracarboxylate oligomeric and polymer complexes of technetium was proposed. Stable oligomeric tetracarboxylate technetium clusters formed in acetic acid solutions can be used to create radiopharmaceuticals. (c) 2021 Elsevier B.V. All rights reserved.
查看更多>>摘要：Treatment of [RuCl2(dmso)(4)] (dmso = dimethyl sulfoxide) with ferrocenylformyl acetone and ferrocenyl enaminone Fc-C(O)CH=C(CH3)N(H)CH2CH2NH2 (Fc = ferrocenyl, HL1) in a 1:1:1 molar ratio in the presence of CH3ONa in methanol afforded a ruthenium(II) complex [(Fc-C(O)CHC(O)CH3)Ru(dmso)(L1)] (1) with a pi-conjugated tridentate Schiff base ligand and a [(Fc-C(O)CHC(O)CH3)](-)ligand. Similar reactions between [RuCl2(dmso)(4)] and Fc-C(O)CH=C(CH3)N(H)Ar (Ar = C6H5, HL2; Ar = 4-ClC6H4, HL3; Ar = 2-MeC6H4, HL4; Ar = 2-OMeC6H4, HL5) afforded corresponding ruthenium(II) complexes [Ru(L2)(2)(dmso)(2)] (2), [Ru(L3)(2)(dmso)(2)] (3), [Ru(L4)(2)(dmso)(2)] (4), and [Ru(L5)(2)(dmso)(2)] (5) with pi-conjugated bidentate Schiff base ligands. Complexes 1-5 were well characterized by infrared, UV/Vis and NMR spectroscopies along with their electrochemical properties. The molecular structure of complex 1 center dot Et2O has been established by single-crystal X-ray diffraction. The photocatalytic properties for H-2 evolution by reduction of water of complexes 1-5 were also investigated in the paper. (C) 2021 Elsevier B.V. All rights reserved.
查看更多>>摘要：The Pd catalyzed cross-coupling reactions have played a crucial role in accomplishing different valuable organic transformations. These transformations involve the use of homogeneous as well as heterogeneous Pd catalysts. A large variety of ligands have been used in Pd catalyzed coupling reactions. Traditionally, these transformations have been carried out by various phosphine-based ligands. The phosphine ligands are suffering from poor air, moisture, and thermal stability. Hence, in recent years phosphine-free ligands such as N-heterocyclic carbenes and amines have been attracted great attention in the field of catalysis. Though the N-containing ligands have showed comparatively low activity as compared to phosphine and carbene-based ligands, most importantly, these complexes have broad scope in catalysis, as they represent a low cost, less toxic, good moisture, thermal and air stability as well as environmentally friendly. In this review, we present the developments made in the field of Pd complexes of N and O donor ligands in various cross-coupling reactions. (c) 2021 Elsevier B.V. All rights reserved.
Moorthy, ShrutiTyagi, AdishTorubaev, YuryButcher, Raymond J....
11页
查看更多>>摘要：In the present report, the reactivity of the binuclear complex [Ni-2(mu-SeC5H4N)(2)(dppe)(2)](2+) towards dichloromethane and methanol has been studied. The complex [Ni-2(mu-SeC5H4N)(2)(dppe)(2)](2+) in the pres-ence of chlorinated solvent resulted in selenido bridged trinuclear complex of composition [Ni-3(mu-Se)(2)(dppe)(2)](2+) (1) whereas in the presence of methanol hydrolyzed product having cubane core [Ni-4{(C5H4N)(2)Se}(4)(mu(3)-OH)(4)(C6H5COO)(HCOO)](2+) (2) was isolated. Both the complexes were characterized by elemental analysis, IR, H-1, and P-31{H-1} NMR spectroscopy. An attempt has also been made to inves-tigate their thermal studies. The molecular structure of both the complex [Ni-3(mu-Se)(2)(dppe)(2)](2+) (1) and [Ni-4{(C5H4N)(2)Se}(4)(mu(3)-OH)(4)(C6H5COO)(HCOO)](2+) (2) were established by single-crystal X-ray diffraction analysis. Broken-symmetry density functional theory (BS-DFT) calculations were carried out on complex 2 to investigate the electronic structure and nature of magnetic exchange interaction. BS-DFT reveals the existence of three different J values i.e. -8.9 cm(-1), + 18.7 cm(-1) and + 1.8 cm(-1) between different Ni(II) pairs. A strong ferromagnetic interaction was observed between formate/phenylacetate bridged Ni(II) cen-ters. An antiferromagnetic interaction between the ferromagnetically coupled formate and phenylacetate bridged Ni(II) dimers result in isolation of S = 0 spin ground state for complex 2 . Molecular orbital, spin-density analyses were performed on the X-ray and optimized geometries to probe the electronic structure of complex 2 . (C) 2021 Elsevier B.V. All rights reserved.
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