1,255 research outputs found

    (E)-1-{6-[1-(2,6-Dimethyl­phenyl­imino)­eth­yl]pyridin-2-yl}ethanone

    Get PDF
    In the title compound, C17H18N2O, the dijedral angle between the mean planes of the pyridine and benzene rings is 78.0 (1)°. In the crystal, pairs of C—H⋯O inter­actions with graph-set motif R 2 2(10) form inversion dimers. Adjacent dimers are further connected into a three-dimensional network by C—H⋯O connections. There is also an inter­action between the carbonyl groups in adjacent mol­ecules with an O⋯C distance of 3.176 (2) Å

    Oxygen insertion into metal carbon bonds: formation of methylperoxo Pd(II) and Pt(II) complexes via photogenerated dinuclear intermediates

    No full text
    Platinum(II) and palladium(II) complexes [M(CH₃)(L)]SbF₆ with substituted terpyridine ligands L undergo light-driven oxygen insertion reactions into metal methyl bonds resulting in methylperoxo complexes [M(OOCH₃)(L)]SbF₆. The oxygen insertion reactions occur readily for complexes with methyl ligands that are activated due to steric interaction with substituents (NH₂, NHMe or CH₃) at the 6,6″-positions on the terpyridine ligand. All complexes exhibit attractive intermolecular π···π or M···M interactions in the solid state and in solution, which lead to excited triplet dinuclear M–M complexes upon irradiation. A mechanism is proposed whereby a dinuclear intermediate is generated upon irradiation that has a weakened M–C bond in the excited state, resulting in the observed oxygen insertion reactions

    Dichlorido{2-[(thio­phen-2-ylmeth­yl)imino­meth­yl]pyridine-κ2 N,N′}palladium(II)

    Get PDF
    In the title compound, [PdCl2(C11H10N2S)], the PdII ion is four-coordinated in a distorted square-planar environment by two N atoms of the chelating 2-[(thio­phen-2-ylmeth­yl)imino­meth­yl]pyridine ligand and two chloride anions. The thio­phene ring is rotationally disordered over two orientations in a 1:1 ratio. The crystal packing exhibits weak inter­molecular C—H⋯Cl and C—H⋯S hydrogen bonds

    2,6-Bis[1-(2-isopropyl­phenyl­imino)­ethyl]­pyridine

    Get PDF
    The title compound, C27H31N3, has E substitution at each imine double bond where the two N atoms adopt a trans–trans relationship. The benzene rings are twisted out of the mean plane of the pyridine ring; the mean planes of the aromatic groups are rotated by 63.0 (1) and 72.58 (8)°. The crystal structure is sustained mainly by C—H⋯π and hydro­phobic methyl–methyl inter­actions

    N

    Get PDF

    The mathematics of ethylene oligomerisation and polymerisation

    Get PDF
    Linear α-olefins or LAOs are produced by the catalytic oligomerisation of ethylene on a multimillion ton scale annually. A range of LAOs is typically obtained with varying chain lengths which follow a distribution. Depending on the catalyst, various types of distributions have been identified, such as Schulz–Flory, Poisson, alternating and selective oligomerisations such as ethylene trimerisation to 1-hexene and tetramerisation to 1-octene. A comprehensive mathematical analysis for all oligomer distributions is presented, showing the relations between the various distributions and with ethylene polymerisation, as well as providing mechanistic insight into the underlying chemical processes. Linear α-olefins or LAOs are produced by the catalytic oligomerisation of ethylene on a multimillion ton scale annually. A range of LAOs is typically obtained with varying chain lengths which follow a distribution. Depending on the catalyst, various types of distributions have been identified, such as Schulz–Flory, Poisson, alternating and selective oligomerisations such as ethylene trimerisation to 1-hexene and tetramerisation to 1-octene. A comprehensive mathematical analysis for all oligomer distributions is presented, showing the relations between the various distributions and with ethylene polymerisation, as well as providing mechanistic insight into the underlying chemical processes

    Monitoring light‐driven oxygen insertion reactions into metal carbon bonds by LED‐NMR spectroscopy

    Get PDF
    The facile light-driven insertion reaction of oxygen into metal carbon bonds of the BPI (1,3-bis(2-pyridylimino)isoindole) complexes [Pt(BPI)Me] and [Pd(BPI)Me] has been investigated by LED-NMR in CDCl3. The initial insertion reaction leads to peroxo complexes [Pt(BPI)OOMe] and [Pd(BPI)OOMe], which undergo further reactions over time. Spectra were recorded at 1 minute time intervals, which enabled the tracking of the methyl substituent, which eventually generates formaldehyde (and methanediol) and methanol in almost equal proportions. Degradation of the solvent CDCl3 to phosgene and DCl in the presence of oxygen and light leads to several side reactions. DCl reacts with [M(BPI)Me] and [M(BPI)OOMe] to form [M(BPI)Cl], whereas phosgene reacts with in situ generated methanol to chloro methylformate and dimethyl carbonate
    corecore