Bis(1H-pyrazole-κN 2)bis­(2,4,6-tri­isopropyl­benzoato-κO)cobalt(II)

The title compound, [Co(C16H23O2)2(C3H4N2)2] or (C3H4N2)2Co(O2CC6H2 iPr3-2,4,6), is a rare example of a tetra­coordinate cobalt(II) carboxyl­ate stabilized by ancillary N-heterocyclic ligands. The Co(II) ion resides on a crystallographic twofold axis so that the asymmetric unit comprises one half-mol­ecule. Due to the steric bulk of the 2,4,6-triisopropyl­phenyl substituents, the carboxyl­ate ligands are both coordinated in a monodentate fashion despite the low coordination number. The coordination geometry around the central Co(II) ion is distorted tetra­hedral with angles at Co ranging from 92.27 (18)° to 121.08 (14)°

Bis({tris[2-(3,5-di-tert-butyl-2-oxido­benzylideneamino)ethyl]amine}cerium(III)) diethyl ether solvate

The title compound, 2[Ce(C51H75N4O3)]·C4H10O, was obtained in high yield (92%) by reduction of (TRENDSAL)CeIVCl [TRENDSAL is N,N′,N′′-tris­(3,5-di-tert-butyl­salicyl­ide­natoamino)­triethyl­amine] with potassium in THF. The bulky tripodal TRENDSAL ligand effectively encapsulates the central CeIII cation with a Ce—N(imine) distance of 2.860 (2) Å and an average C—N(amine) distance of 2.619 Å within a distorted monocapped octahedral coordination

Tris(N,N′-diisopropyl­benzamidinato)cerium(III)

The title compound, [Ce(C13H19N2)3], was obtained in moderate yield (67%) by treatment of anhydrous cerium trichloride with three equivalents of Li[PhC(NiPr)2] in tetra­hydro­furan. It is the first homoleptic lanthanide complex of this amidinate ligand. The central CeIII ion is coordinated by three chelating benzamidinate anions in a distorted octa­hedral fashion, with Ce—N distances in the narrow range 2.482 (2)–2.492 (2) Å. The dihedral angles between the phenyl rings and the chelating N—C—N units are in the range 73.3–87.9°, thus preventing conjugation between the two π-systems. The mol­ecule is located on a twofold rotation axis, and one of the phenyl rings is equally disordered over two alternative symmetry-equivalent positions around this axis

trans-Bis(perchlorato-κO)tetra­kis(1H-pyrazole-κN 2)copper(II)

The title compound, [Cu(ClO4)2(C3H4N2)4], was obtained unexpectedly by the reaction of copper(II) perchlorate hexa­hydrate with equimolar amounts of 1-chloro-1-nitro-2,2,2-tripyrazolylethane in methanol solution. The crystal structure comprises octa­hedrally coordinated Cu2+ ions, located on an inversion centre, with four pyrazole ligands in the equatorial plane. The average Cu—N distance is 2.000 (1) Å. Two perchlorate ions are coordinated to copper in trans positions [Cu—O = 2.4163 (11) Å]

[{μ-Cy 8 Si 8 O 13 } 2 Ca(DME)Ca(THF) 2 ] ؊ The First Metallasilsesquioxane Derivative of a Heavier Alkaline Earth Metal

Abstract. [{μ-Cy 8 Si 8 O 13 } 2 Ca(DME)Ca(THF) 2 ] (2), the first metallasilsesquioxane derivative of a heavier alkaline earth metal, has been prepared by a reaction of Cy 7 Si 7 O 9 (OH) 3 (1) with metallic Ca in liquid ammonia / THF followed by recrystallization from DME. In the course of the reaction ligand rearrangement under formation of the (Cy 8 Si 8 O 13 ) Ϫ dianion takes place. In the dinuclear calciu

1,2,3,4-Tetra­methyl­cyclo­pent-2-ene-1,4-diol

The title compound, C9H16O2, crystallizes with two mol­ecules in the asymmetric unit. The structure displays inter­molecular O—H⋯O hydrogen bonding

1,2,3-Triphenyl-1,2-dihydro­quinoxaline

The title compound, C26H20N2, first reported in 1891, was obtained as a by-product in the preparation of benzildianil from benzil and excess aniline. The dihedral angles between the fused benzene ring and the pendant phenyl rings are 17.93 (11), 53.18 (10) and 89.08 (12)°

Synthesis and Complexation Study of New Aminoalkynyl−amidinate Ligands

Abstract The current library of amidinate ligands has been extended by the synthesis of two novel dimethylamino‐substituted alkynylamidinate anions of the composition [Me 2 N−CH 2 −C≡C−C(NR) 2 ] − (R = i Pr, cyclohexyl (Cy)). The unsolvated lithium derivatives Li[Me 2 N−CH 2 −C≡C−C(NR) 2 ] ( 1 : R = i Pr, 2 : R = Cy) were obtained in good yields by treatment of in situ‐ prepared Me 2 N−CH 2 −C≡C−Li with the respective carbodiimides, R−N=C=N−R. Recrystallization of 1 and 2 from THF afforded the crystalline THF adducts Li[Me 2 N−CH 2 −C≡C−C(NR) 2 ] ⋅  n THF ( 1 a : R = i Pr, n =1; 2 a : R = Cy, n =1.5). Precursor 2 was subsequently used to study initial complexation reactions with selected di‐ and trivalent transition metals. The dark red homoleptic vanadium(III) tris(alkynylamidinate) complex V[Me 2 N−CH 2 −C≡C−C(NCy) 2 ] 3 ( 3 ) was prepared by reaction of VCl 3 (THF) 3 with 3 equiv. of 2 (75 % yield). A salt‐metathesis reaction of 2 with anhydrous FeCl 2 in a molar ratio of 2 : 1 afforded the dinuclear homoleptic iron(II) alkynylamidinate complex Fe 2 [Me 2 N−CH 2 −C≡C−C(NCy) 2 ] 4 ( 4 ) in 69 % isolated yield. Similarly, treatment of Mo 2 (OAc) 4 with 3 or 4 equiv. of 2 provided the dinuclear, heteroleptic molybdenum(II) amidinate complex Mo 2 (OAc)[Me 2 N−CH 2 −C≡C−C(NCy) 2 ] 3 ( 5 ; yellow crystals, 50 % isolated yield). The cyclohexyl‐substituted title compounds 2 a , 4 , and 5 were structurally characterized through single‐crystal X‐ray diffraction studies.imag

Corrigendum to ‘‘Alumino-mesostructured Ni catalysts for the direct conversion of ethene to propene” [J. Catal. 305 (2013) 154–168]

Ni/MCM-41 and Ni/AlMCM-41 were synthesized at different Si/Al ratios and tested in the direct conversion of ethene to propene (ETP-reaction). It was intended to evaluate the effect of modifying the catalyst acidity on the ETP-reaction rather than optimizing its performance. All catalysts were characterized by powder XRD, N2-physisorption, 29Si and 27Al MAS NMR, TEM, NH3-TPD, pyridine-DRITFS, H2-TPR, and TPO. Ni/MCM-41 showed low catalytic activity due to its low acidity. Ni/AlMCM-41 catalyst with a Si/Al ratio of 60 had high catalytic activity. Characterization results revealed that the catalyst structure does not have effect on the catalytic activity. Al could be incorporated into the MCM-41 framework up to Si/Al ratio of 16. Two different Ni-composites on the surface of the MCM-41 and AlMCM-41 were observed. Deeper characterization is required to know the Ni state. Important deactivation was observed at 450 °C. The nature of the carbonaceous species and reaction mechanism require deeper characterization