Reference

Preparation and molecular structure of a dinuclear rhodium complex having an unbalanced (15+17)-electron count

Preparation and molecular structure of a dinuclear rhodium complex having an unbalanced (15+17)-electron count. Herber, Ulrich; Ilg, Kerstin; Werner, Helmut (Institut fuer Anorganische Chemie, Universitaet Wuerzburg, Wuerzburg D-97074, Germany). Journal of Organometallic Chemistry, 689(26), 4917-4920 (English) 2004 Elsevier B.V. CODEN: JORCAI. ISSN: 0022-328X. DOCUMENT TYPE: Journal CA Section: 29 (Organometallic and Organometalloidal Compounds) Section cross-reference(s): 75 The reaction of [Rh2(acac)2{m-C(p-tol)2}2(m-SbiPr3)] (1) with PMe3 led to the displacement of the stibine by phosphine and afforded the highly labile intermediate [Rh2(acac)2(PMe3){m-C(p-tol)2}2] (2) in which the PMe3 ligand possibly occupies a terminal position. Treatment of 2 with CO at low temps. gave the unsym. 594-09-2 and 412941-32-3 which are cas registry numbers of chemicals are mentioned. dinuclear complex [Rh2(acac)2(PMe3){m-C(p-tol)2}2(m-CO)] (3), the mol. structure of which was detd. crystallog. .

Characterization of acidity in zeolites and related oxides using trimethylphosphine as a probe

Characterization of acidity in zeolites and related oxides using trimethylphosphine as a probe. Lunsford, Jack H. (Department of Chemistry, Texas AandM University, College Station, TX 77843, USA). Topics in Catalysis, 4(1,2, Acidity in Aluminas, Amorphous and Crystalline Silico-Aluminas), 91-98 (English) 1997 Baltzer. CODEN: TOCAFI. ISSN: 1022-5528. DOCUMENT TYPE: Journal; General Review CA Section: 67 (Catalysis, Reaction Kinetics, and Inorganic Reaction Mechanisms) Section cross-reference(s): 77 A review with 26 refs.; the MAS-NMR spectra of trimethylphosphine (TMP) have been used to study acidity on zeolites, amorphous silica-alumina, sulfated zirconia and other solid materials. Acidic protons react with the strong Lewis base to form [(CH3)3P-H]+ adducts that are characterized by a 31P chem. shift of ca. -3 ppm and a JP-H coupling const. of ca.In this article, certain chemicals are used. One of their cas registry numbers is 594-09-2 500 Hz. Lewis-bound TMP exhibits resonances at considerably higher fields, and if aluminum is involved, a JP-A1 coupling of ca. 300 Hz may result in a multiplet of six lines. When excess TMP is present, rapid chem. exchange may occur between the liq.-like mols. and those that are complexed at acid sites. In such cases the distinction between the different forms of TMP is obscured. Attempts to relate Bronsted acid strength to a magnetic parameter such as the scalar coupling const. show promise in those cases where the majority species is of interest. In dealuminated Y zeolites, however, it appears that a small fraction of the protons is responsible for acid-catalyzed reactions, and the value of the JP-H coupling does not adequately reflect the contribution of these centers. .