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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]

Nine new cobalt(II) compounds, trans-[Co(LPAQ)2(Py)2] (1), trans-[Co(LPAQ)2(3-MePy)2] (2), trans-[Co(LMeAQ)2(Py)2] (3), trans-[Co(LOMeAQ)2(Py)2] (4), trans-[Co(LOEtAQ)2(Py)2]·2(H2O) (5), trans-[Co(LCAQ)2(Py)2] (6), trans-[Co(LBAQ)2(Py)2] (7), cis-[Co(LBAQ)2(3-MePy)2] (8a) and trans-[Co(LBAQ)2(3-MePy)2]·2(3-MePy) (8b) (primary ligand: LXAQ = substituted 5-[(E)-2-(aryl)-1-diazenyl]quinolin-8-olate; secondary ligands: Py = pyridine, 3-MePy = 3-methylpyridine), have been synthesized and characterized by elemental analysis, IR and UV-vis spectroscopy. Magnetic measurements of the cobalt compounds were performed in solution by 1H NMR spectroscopy using the Evans' method while their redox properties were studied by cyclic voltammetry. Single-crystal X-ray diffraction analysis of the compounds revealed their octahedral geometries and trans configuration, except for 8a, which has a cis configuration. Intermolecular noncovalent interactions were detected, π···π interactions in 5, C - H···π interactions in 2 and C - H···π edge-to-face (T-shaped) arrangements in 3, 4, 6, and 7. [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 experimental conditions (solvent, base, temperature and oxidant) for allylic and benzylic oxidation reactions catalyzed by dirhodium(II)/N-heterocyclic carbene (NHC) complexes were optimized for the first time in this work. The oxidations of cyclohexene and fluorene were used as model reactions. Two optimized experimental conditions for both types of oxidations were found, which resulted in their ketone [aerobic conditions, 40 °C, 1 equiv. tBuOOH (TBHP)] or tert-butyl peroxide derivatives (anaerobic conditions, 25 °C, 2 equiv. TBHP). The dirhodium(II) complexes undergo a single-electron reversible oxidation by cyclic voltammetry in CH2Cl2, which is assigned to the Rh24+/Rh25+ redox couple at an oxidation potential that is lowered upon sequential axial coordination of further ligands to the Rh-Rh centre. The oxidation potential is discussed in terms of the electron-donor character of the NHC ligand, which was shown to act as an effective electron-releaser to the Rh24+ centre, and the electrochemical behaviour is compared to the observed catalytic activity. [ABSTRACT FROM AUTHOR]

Reaction of the o-[(o-hydroxyphenyl)methylideneamino]benzenesulfonic acid (H2L) (1) with CuCl2·2H2O in the presence of pyridine (py) leads to [Cu(L)(py)(EtOH)] (2) which, upon further reaction with 2,2'-bipyridine (bipy), pyrazine (pyr), or piperazine (pip), forms [Cu(L)(bipy)]·MeOH (3), [Cu2(L)2(μ-pyr)(MeOH)2] (4), or [Cu2(L)2(μ-pip)(MeOH)2] (5), respectively. The Schiff base (1) and the metal complexes (2–5) are stabilized by a number of non-covalent interactions to form interesting H-bonded multidimensional polymeric networks (except 3), such as zigzag 1D chain (in 1), linear 1D chain (in 2), hacksaw double chain 1D (in 4) and 2D motifs (in 5). These copper(II) complexes (2–5) catalyze the peroxidative oxidation of cyclic hydrocarbons (cyclooctane, cyclohexane, and cyclohexene) to the corresponding products (alcohol and ketone from alkane; alcohols, ketone, and epoxide from alkene), under mild conditions. For the oxidation of cyclooctane with hydrogen peroxide as oxidant, used as a model reaction, the best yields were generally achieved for complex 3 in the absence of any promoter (20%) or in the presence of py or HNO3 (26% or 30%, respectively), whereas 2 displayed the highest catalytic activity in the presence of HNO3 (35%). While the catalytic reactions were significantly faster with py, the best product yields were achieved with the acidic additive. [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.)

This work describes the preparation of a series of platinum-aminocarbene complexes [PtCl{C(N=C a (C 6 R 2 R 3 R 4 R 5 CON b ))=N(H)R 1 }(CNR 1 )] a-b ( 8 - 19 , 65-75% isolated yield) via the reaction of cis -[PtCl 2 (CNR 1 ) 2 ] (R 1 = Cy 1 , t -Bu 2 , Xyl 3 , 2-Cl-6-MeC 6 H 3 4 ) with 3-iminoisoindolin-1-ones HN=C a (C 6 R 2 R 3 R 4 R 5 CON b H) (R 2 -R 5 = H 5 ; R 3 = Me, R 2 , R 4 , R 5 = H 6 ; R 3 , R 4 = Cl, R 2 , R 5 = H 7 ). New complexes 17 - 19 were characterized by elemental analyses (C, H, N), ESI + -MS, Fourier transform infrared spectroscopy (FT-IR), one-dimensional ( 1 H, 13 C{ 1 H}), and two-dimensional ( 1 H, 1 H correlation spectroscopy (COSY), 1 H, 13 C heteronuclear multiple quantum correlation (HMQC)/ 1 H, 13 C heteronuclear single quantum coherence (HSQC), 1 H, 13 C heteronuclear multiple bond correlation (HMBC)) NMR spectroscopy, and authenticity of known species 8 - 16 was confirmed by FT-IR and 1 H and 13 C{ 1 H} NMR. Complexes 8 - 19 were assessed as catalysts for hydrosilylation of terminal alkynes with hydrosilanes to give vinyl silanes, and complex [PtCl{C(N=C a (C 6 H 3 (5-Me)CON b ))=N(H)(2-Cl-6-MeC 6 H 3 )}{CN(2-Cl-6-MeC 6 H 3 )}] a - b ( 18 ) showed the highest catalytic activity. The catalytic system proposed operates at 80-100 °C for 4-6 h in toluene and with catalyst loading of 0.1 mol %, enabling the reaction of a number of terminal alkynes (PhC≡CH, t -BuC≡CH, and 4-( t -Bu)C 6 H 4 C≡CH) with hydrosilanes (Et 3 SiH, Pr 3 SiH, i -Pr 3 SiH, and PhMe 2 SiH). Target vinyl silanes were prepared in 48-95% yields (as a mixture of α/β isomers) and with maximum turnover number of 8.4 × 10 3 . Hydrosilylation of internal alkynes (PhC≡CPh, Me(CH 2 ) 2 C≡C(CH 2 ) 2 Me, and PhC≡CMe) with hydrosilanes (Et 3 SiH, PhMe 2 SiH) led to the corresponding trisubstituted silylated alkenes in 86-94% yields. Initial observations on the mechanism of the catalytic action of platinum-ADC catalysts 8 - 19 suggested a molecular catalytic cycle., Competing Interests: The authors declare no competing financial interest.

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.)