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    ABSTRACT: The calcium-catalyzed intramolecular hydroamination of alkenes and alkynes is reported. The beta-diketiminato complex [{HC(C(Me)2N-2,6-iPr2C6H3)2}-Ca{N(SiMe3)2}(THF)] affects catalytic cyclization of a range of aminoalkenes and aminoalkynes with activities that are broadly commensurate to those of established rare earth catalysts.
    Journal of the American Chemical Society 03/2005; 127(7):2042-3. · 10.68 Impact Factor
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    ABSTRACT: The lattice energies of the 20 binary compounds composed of Be++, Mg++, Ca++, Sr++, Ba++, O-, S-, Se- and Te- have been computed by previously well-tested procedures. Because of lack of sufficiently reliable compressibility data, the computations have been made with two different assumptions regarding the magnitude of the constant a in the exponent of the repulsion energy term. These two assumptions yield lattice energies which differ, in most cases, by about 20 kcal. In general, a single value of the ``constant energy radius'' suffices for each type of ion. For the beryllium compounds, however, it was necessary to use different radii for the Be++ ion for each compound. In MgTe also, a slightly different Mg++ radius from that deduced for the other magnesium compounds was required. These irregularities may be related to the fact that these crystals have ``tetrahedral'' structures, unlike the others, with significant but unknown amounts of covalent bonding. The characteristic constants deduced should be useful in the theoretical treatment of many properties dependent on interactions between ions, both in these crystals and in other systems. For these crystals, the interionic distances, compressibilities and maximum infrared lattice-vibration frequencies have been computed. By combining the computed lattice energies with thermochemical data, electron affinities (for the addition of two electrons to each of the electro negative atoms) have been computed and compared. Based on these results, the authors' best estimates, in kcal/mole, are as follows: O, -162± 15; S, -99± 15; Se, -117± 15; Te, -97± 20.
    Journal of The Physical Society of Japan - J PHYS SOC JPN. 01/1957; 12(3):241-251.
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    ABSTRACT: For Abstract see ChemInform Abstract in Full Text.
    Chemical Reviews 08/2003; 103(7):2579-95. · 41.30 Impact Factor