Aerobic oxidation of alcohols are catalyzed by the Pd-acetate compound [LPd(OAc)]2(OTf)2 (L = neocuproine = 2,9-dimethyl-1,10-phenanthroline) to form ketones and the release of hydrogen peroxide, but the latter rapidly undergoes disproportionation. We employ a series of kinetic and isotope labeling studies made largely possible by electrospray ionization mass spectrometry to determine the role ...

A binuclear tungsten(0) complex with an asymmetric bridging 1,2-diphosphole ligand was prepared by the photolysis of tungsten hexacarbonyl in presence 1-isopropyl-2-phenyl-1,2,5,6-tetrahydroacenaphtho [5,6-cd][1,2]diphosphole. The 1 characterized high resolution mass spectrometry, multinuclear NMR spectroscopy (1H, 13C, 31P), and elemental microanalysis. structure trans isomer resolved single c...

Two novel Sb(III) and Sb(V) peri-substituted acenaphthene phosphorus−antimony compounds were prepared. The compound, 1, was prepared via reacting the organolithium precursor with dichloro(p-tolyl)Stibine, 2 by chlorination of 1. Both 1 characterized multinuclear (1H, 13C 31P) NMR spectroscopy, their molecular structures resolved single-crystal X-ray diffraction. show a dative P−Sb interaction a...

We have observed a disturbing suppression effect in three-pulse ESEEM and HYSCORE spectra of systems with more than one nucleus coupled to the electron spin. For such systems, the ESEEM signal contains internuclear combination peaks of varying intensity. At the same time, the peaks at the basic ESEEM frequencies are reduced in intensity, up to the point of complete cancellation. For both three-...

PURPOSE Multinuclear magnetic resonance spectroscopy and imaging require a radiofrequency probe capable of transmitting and receiving at the proton and non-proton frequencies. To minimize coupling between probe elements tuned to different frequencies, LC (inductor-capacitor) traps blocking current at the (1)H frequency can be inserted in non-proton elements. This work compares LC traps with LCC...

Nearly all atoms contributing to the local structure of Bransted acid sites in zeolites exhibit isotopes accessible for multinuclear solid-state nuclear magnetic resonance (NMR) investigations. Therefore, in the last 15 years, NMR spectroscopy has found numerous applications for the determination of the types of hydroxyl proton in zeolites, of their concentration, accessibility, and mobility, a...

Preparation and characterization of two new triptycene based polytopic Pt(II) organometallic complexes are being reported. These complexes have three trans-bromobis(trialkylphosphine)platinum(II) units directly attached to the central triptycene unit. These organoplatinum complexes were converted to the corresponding nitrate salts for subsequent use in self-assembly reactions. Characterization ...

Multinuclear manganese sites that are involved in the catalysis of reactions vital to biological systems are being steadily recognized and studied. Besides the photosynthetic water-oxidizing complex, which is known to utilize 4 Mn ions for the oxidation of water to molecular oxygen [1], evidence has accumulated that the Mn site of the pseudo-catalase from Lactobacillus planatrum is comprised of...

OBJECTIVES To analyse some scavenging related molecules in Wegener's granulomatosis (WG) macrophages. METHODS Immunohistochemical staining of lung, nasopharynx, and skin for macrophage markers related to scavenging (macrophage scavenger receptor MARCO, collagenase-1 and gelatinase-B), formation of multinuclear foreign body giant cells (ADAM 9/meltrin-gamma and ADAM 12/meltrin-alpha), and cell...

The capabilities and limitations of the Becke-3-Lee-Yang-Parr (B3LYP) hybrid density functional are investigated as applied to studies of mixed-valent multinuclear oxomanganese complexes. Benchmark calculations involve the analysis of structural, electronic and magnetic properties of di-, tri- and tetra-nuclear Mn complexes, previously characterized both chemically and spectroscopically, includ...