3,5-Bis(4-chloro­benzyl­idene)-1-methyl­piperidin-4-one

In the title mol­ecule, C20H17Cl2NO, the central heterocyclic ring adopts a flattened boat conformation. The dihedral angles between the planar part of this central heterocyclic ring [maximum deviation = 0.004 (1) Å] and the two almost planar side-chain fragments [maximum deviations = 0.015 (1) and 0.019 (1) Å], that include the aromatic ring and bridging atoms, are 18.1 (1) and 18.0 (1)°. In the crystal, pairs of weak inter­molecular C—H⋯O hydrogen bonds link mol­ecules into inversion dimers that form stacks along the a axis. The structure is further stabilized by weak inter­molecular C—H⋯π inter­actions involving the benzene rings

1-Benzyl-3,5-bis­(4-chloro­benzyl­idene)piperidin-4-one

The title compound, C26H21Cl2NO, crystallizes with two symmetry-independent mol­ecules (A and B) in the asymmetric unit. In both mol­ecules, the central heterocyclic ring adopts a sofa conformation. The dihedral angles between the planar part of this central heterocyclic ring [maximum deviations of 0.011 (1) and 0.036 (1) Å in mol­ecules A and B, respectively] and the two almost planar [maximum deviations of 0.020 (1) and 0.008 (1) Å in A and 0.007 (1) and 0.011 (1) in B] side-chain fragments that include the aromatic ring and bridging atoms are 20.1 (1) and 31.2 (1)° in mol­ecule A, and 26.4 (1) and 19.6 (1)° in mol­ecule B. The dihedral angles between the planar part of the heterocyclic ring and the benzyl substituent are 79.7 (1) and 53.2 (1)° in mol­ecules A and B, respectively. In the crystal, weak inter­molecular C—H⋯O hydrogen bonds link the two independent mol­ecules into dimers

Crystal structure of (3E,5E)-3,5-bis[4-(diethylazaniumyl)benzylidene]-1-methyl-4-oxopiperidin-1-ium trichloride dihydrate: a potential biophotonic material

This article describes the crystal structure of the title compound, and examines application as an agent for locating cancer cells with two-photon excited fluorescence as as a potential agent for a photodynamic treatment of cancer. This article includes supporting information with computing details of the study

N,N-Dimethyl-N'-[(1E,2E)-3-(4-nitrophenyl)prop-2-enylidene]benzene-1,4-diamine and N,N-dimethyl-4-[(1E,3E)-4-(4-nitrophenyl)buta-1,3-dienyl]-1-naphthylamine

© 2003 International Union of CrystallographyDOI: 10.1107/S0108270103020985Syntheses and X-ray structural investigations have been carried out for the two title compounds, viz. C(17)H(17)N(3)O(2), (I), and C(22)H(20)N(2)O(2), (II). The molecular skeleton of (I) is slightly non-planar; the dihedral angles between the conjugated linkage and the p-(dimethylamino)phenyl ring, and between the linkage and the p-nitrophenyl ring are 13.0 (2) and 13.8 (2) degrees, respectively. The dihedral angle between the slightly pyramidal dimethylamine substituent and the aromatic ring is 23.3 (1) degrees. The molecular skeleton of (II) is not planar; the dihedral angles between the conjugated linkage and the naphthalene ring, and between the linkage and the substituted phenyl ring are 36.1 (2) and 2.7 (3) degrees, respectively. The dimethylamine substituent in (II) has a pyramidal geometry; the dihedral angle between this substituent and the naphthalene ring is 71.7 (1) degrees. The dihedral angle between the nitro group and the plane of the substituted phenyl ring is 9.0 (3) degrees. There is a weak intermolecular C-H.O hydrogen bond in the crystal structure of (II), which links the molecules into centrosymmetric dimers. Molecular mechanics calculations of molecular conformations have shown that the crystal environment influences the conformation more in (I) than in (II)

Heterometallic Co^III₄Fe^III₂ Schiff Base Complex: Structure, Electron Paramagnetic Resonance, and Alkane Oxidation Catalytic Activity

The heterometallic complex [Co₄Fe₂OSae₈]·4DMF·H₂O (<b>1</b>) was synthesized by one-pot reaction of cobalt powder with iron chloride in a dimethylformamide solution of salicylidene-2-ethanolamine (H₂Sae) and characterized by single crystal X-ray diffraction analysis, magnetic measurements, high frequency electron paramagnetic resonance (HF-EPR), and Mössbauer spectroscopies. The exchange coupling in the Fe­(III)–Fe­(III) pair is of antiferromagnetic behavior with <i>J</i>/<i>hc</i> = −190 cm^–1. The HF-EPR spectra reveal an unusual pattern with a hardly detectable triplet signal of the Fe­(III) dimer. The magnitude of <i>D</i> (ca. 13.9 cm^–1) was found to be much larger than in related dimers. The catalytic investigations disclosed an outstanding activity of <b>1</b> toward oxidation of cycloalkanes with hydrogen peroxide, under mild conditions. The most efficient system showed a turnover number (TON) of 3.57 × 10³ with the concomitant overall yield of 26% for cyclohexane, and 2.28 × 10³/46%, respectively, for cyclooctane. A remarkable turnover frequency (TOF) of 1.12 × 10⁴ h^–1 (the highest initial rate <i>W</i>₀ = 3.5 × 10^–4 M s^–1) was achieved in oxidation of cyclohexane. Kinetic experiments and selectivity parameters led to the conclusion that hydroxyl radicals are active (attacking C–H bonds) species. Kinetic and electrospray ionization mass spectrometry (ESI-MS) data allowed us to assume that the trinuclear heterometallic particle [Co₂Fe­(Sae)₄]⁺, originated from <b>1</b> in solution, could be responsible for efficient generation of hydroxyl radicals from hydrogen peroxide

J/ψ production as a function of charged-particle multiplicity in p–Pb collisions at √sNN = 8.16 TeV

Inclusive J/ψ yields and average transverse momenta in p-Pb collisions at a center-of-mass energy per nucleon pair sNN−−−√ = 8.16 TeV are measured as a function of the charged-particle pseudorapidity density with ALICE. The J/ψ mesons are reconstructed at forward (2.03<ycms<3.53) and backward (−4.46<ycms<−2.96) center-of-mass rapidity in their dimuon decay channel while the charged-particle pseudorapidity density is measured around midrapidity. The J/ψ yields at forward and backward rapidity normalized to their respective average values increase with the normalized charged-particle pseudorapidity density, the former showing a weaker increase than the latter. The normalized average transverse momenta at forward and backward rapidity manifest a steady increase from low to high charged-particle pseudorapidity density with a saturation beyond the average value

Measurement of Λ(1520) production in pp collisions at √s = 7 TeV and p–Pb collisions at √sNN = 5.02 TeV

The production of the Λ(1520) baryonic resonance has been measured at midrapidity in inelastic pp collisions at s√ = 7 TeV and in p-Pb collisions at sNN−−−√ = 5.02 TeV for non-single diffractive events and in multiplicity classes. The resonance is reconstructed through its hadronic decay channel Λ(1520) → pK− and the charge conjugate with the ALICE detector. The integrated yields and mean transverse momenta are calculated from the measured transverse momentum distributions in pp and p-Pb collisions. The mean transverse momenta follow mass ordering as previously observed for other hyperons in the same collision systems. A Blast-Wave function constrained by other light hadrons (π, K, K0S, p, Λ) describes the shape of the Λ(1520) transverse momentum distribution up to 3.5 GeV/c in p-Pb collisions. In the framework of this model, this observation suggests that the Λ(1520) resonance participates in the same collective radial flow as other light hadrons. The ratio of the yield of Λ(1520) to the yield of the ground state particle Λ remains constant as a function of charged-particle multiplicity, suggesting that there is no net effect of the hadronic phase in p-Pb collisions on the Λ(1520) yield