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The title compound, C20H21F3N2O4, features a main twelve-membered difuryl ring with which the furan rings make dihedral angles of 76.14 (5) and 33.81 (5)°. The dihedral angle between the furan rings is 42.55 (7)°. The six-membered nitrogen heterocycle has a twist-boat conformation. In the crystal, pairs of molecules are connected by intermolecular C--H· · ·O interactions, generating an R2 2(14) ring motif. These pairs of molecules form zigzag chains along the aaxis direction by means of C--H· · ·F interactions. Furthermore, C--H· · ·π and C-F· · ·π interactions link the molecules into chains along the b-axis direction, forming sheets parallel to the (001) plane. These sheets are also connected by van der Waals interactions. [ABSTRACT FROM AUTHOR]

A new (tetrazole-saccharin)nickel complex is shown to be a valuable catalyst for the hydrosilative reduction of aldehydes under microwave radiation at low temperatures. With typical 1 mol% content of the catalyst (microwave power range of 5–15 W) most reactions are complete within 30 min. The Ni(II)-catalyzed reduction of aldehydes, with a useful scope, was established for the first time by using this catalyst, and is competitive with the most effective transition-metal catalysts known for such transformation. The catalyst reveals tolerance to different functional groups, is air and moisture stable, and is readily prepared in straightforward synthetic steps. Supported by experimental data and DFT calculations, a plausible reaction mechanism involving the new catalytic system is outlined. [ABSTRACT FROM AUTHOR]

The NiII and ZnII complexes [MCl(TpmsPh)] (TpmsPh = SO3C(pzPh)3, pz = pyrazolyl; M = Ni 2 or Zn 3) and the CuII complex [CuCl(TpmsPh)(H2O)] (4) have been prepared by treatment of the lithium salt of the sterically demanding and coordination flexible tris(3-phenyl-1-pyrazolyl)methanesulfonate (TpmsPh)-(1) with the respective metal chlorides. The (TpmsPh)-ligand shows the N3 or N2O coordination modes in 2 and 3 or in 4, respectively. Upon reaction of 2 and 3 with Ag(CF3SO3) in acetonitrile the complexes [M(TpmsPh)-(MeCN)](CF3SO3) (M = Ni 5 or Zn 6, respectively) were formed. The compounds were obtained in good yields and characterized by analytic and spectral (IR, ¹H and 13C{¹H} NMR, ESI-MS) data, density functional theory (DFT) methods and {for 4 and [nBu4N](TpmsPh) (7), the latter obtained upon Li+ replacement by [nBu4N]+ in Li(TpmsPh)} by single crystal X-ray diffraction analysis. The ZnII and CuII complexes (3 and 4, respectively) act as efficient catalyst precursors for the diastereoselective nitroaldol reaction of benzaldehydes and nitroethane to the corresponding β-nitroalkanols (up to 99% yield, at room temperature) with diastereoselectivity towards the formation of the anti isomer, whereas the NiII complex 2 only shows a modest catalytic activity. [ABSTRACT FROM AUTHOR]

[RuCl(arene)(μ-Cl)]2 dimers were treated in a 1:2 molar ratio with sodium or thallium salts of bis- and tris(pyrazolyl)borate ligands [Na(Bp [ABSTRACT FROM AUTHOR]

The development of functional materials with uniquely advanced properties lies at the core of nanoscience and nanotechnology. From the myriad possible combinations of organic and/or inorganic blocks, hybrids combining metal nanoclusters and carbon nanomaterials have emerged as highly attractive colloidal materials for imaging, sensing (optical and electrochemical) and catalysis, among other applications. While the metal nanoclusters provide extraordinary luminescent and electronic properties, the carbon nanomaterials (of zero, one or two dimensions) convey versatility, as well as unique interfacial, electronic, thermal, optical, and mechanical properties, which altogether can be put to use for the desired application. Herein, we present an overview of the field, for experts and non-experts, encompassing the basic properties of the building blocks, a systematic view of the chemical preparation routes and physicochemical properties of the hybrids, and a critical analysis of their ongoing and emerging applications. Challenges and opportunities, including directions towards green chemistry approaches, are also discussed., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Synthesis and spectroscopic properties of seven new dibutyltin(IV) compounds of 2-{(E)-4-hydroxy-3-[(E)-4-(aryl)iminomethyl]phenyldiazenyl}benzoic acids (L n HH'; n=2-8) with general formula {[Bu 2 Sn(L n H)] 2 O} 2 (1-7) are reported. The compounds were characterized by elemental analysis and by UV-Visible, fluorescence, IR, 1 H, 13 C and 119 Sn NMR spectroscopies. Solid state structures of dibutyltin(IV) compounds 1-3, 6 and 7 were accomplished from single crystal X-ray crystallography which reveal the common ladder-type structure with two endo- and two exo-Sn atoms. The redox properties of L n HH' (n=2-4, 7 and 8) and their diorganotin(IV) compounds 1-3, 6 and 7 were also investigated by cyclic voltammetry. In general, the dibutyltin(IV) derivatives exhibited significant in vitro cytotoxic potency towards A375 (melanoma) and HCT116 (colon carcinoma) cell lines as determined by several experiments, like Live and Dead assay, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) cell viability assay, LDH (lactate dehydrogenase), cleavage of caspases and PARP (poly(ADP-ribose)polymerase), and DNA fragmentation. Dibutyltin(IV) compounds increase cell death without cytolysis and decreases membrane fluidity, without interfering with p53. Among the dibutyltin(IV) compounds, compound 6 was found to be the most potent, with an IC 50 value of 78nM. A mechanism of action for tumor cell death is proposed., (Copyright © 2016 Elsevier Inc. All rights reserved.)