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11.
Timothy S. Keizer Lauren J. De Pue Sean Parkin David A. Atwood 《Journal of Cluster Science》2002,13(4):609-620
Various Salen ligands (Salen(
t
Bu)H2=N, N-ethylenebis(3,5-di-tertbutyl(2-hydroxy)benzylidenimine) were used to prepare borosilyl and -O bridged borosilyl compounds having the formula, L{B(OSiMe3)2}2 (L=Salen(
t
Bu) (1), Salpen(
t
Bu) (2), Salben(
t
Bu) (3), Salhen(
t
Bu) (4) and L(BOSiMe3)2(-O) (L=Salen(
t
Bu) (5) and Salben(
t
Bu) (6)). In the case of 5 and 6 the formation of the B–O–B linkage takes precedence over the formation of a B–O–Si linkage. All of the compounds were characterized by Mp, elemental analysis, 1H and 11B NMR, IR, MS and in the case of 1, 2, and6 by X-ray crystallography. 相似文献
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The reaction of KCN with Al(CH3)3 to form K[Al(CH3)3CN] is greatly facilitated by the presence of an aromatic solvent: for p-xylene a solid complex, K[Al(CH3)3CN]·C6H4(CH3)2, has been isolated. The crystal structure of potassium cyanotrimethylaluminate has been determined from three-dimensional X-ray data measured by counter methods. K[Al(CH3)3CN] crystallizes in the monoclinic space group C2/c with cell dimensions a = 19.902(7), b = 9.211(4), c = 9.615(4) Å, β = 107.74(5)°, and pcalcd. = 1.09 g cm?1 for Z = 8. Least squares refinement gave a conventional weighted R factor of 4.9% for 807 independent reflections. The monomeric [Al(CH3)3CN]? units possess no crystallographic symmetry, and the packing in the unit cell is such that the nitrogen atoms on three such units approach the potassium atom to within 3.11 Å. The average aluminum-methyl carbon bond distance is 1.971 (7) Å, while the aluminum-cyano carbon distance is 2.047 (7) Å. This significant lengthening is attributed to partial electron deficiency in the aluminum-cyano carbon bond. 相似文献
18.
C. H. Atwood 《Journal of Radioanalytical and Nuclear Chemistry》1993,171(1):225-228
An outline of the 53rd New England Association of Chemistry Teachers Summer Conference is given along with a detailed listing of the conference participants and the lectures presented. Then it is proposed that the Division of Nuclear Chemistry and Technology of the American Chemical Society host similar conferences around the country to influence high school teachers in their teaching of nuclear science. 相似文献
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20.
Ernesto Carmona Jose M. Marin Manuel L. Poveda Robin D. Rogers Jerry L. Atwood 《Journal of organometallic chemistry》1982,238(4):C63-C66
The reduction of [WCl4(PMe3)3] with dispersed sodium, under dinitrogen, gives cis-[W(N2)2(PMe3)4], while under ethylene trans-[W(C2H4)2(PMe3)4] is obtained. The ethylene complex can also be prepared by displacement of the dinitrogen molecules in cis-[W(N2)2(PMe3)4] by ethylene at room temperature and pressure. Interaction of cis-[M(N2)2(PMe3)4] complexes (M = Mo, W), with PMe3, under helium or argon, yields [M(N2)(PMe3)5]. The molybdenum complex crystallizes in the orthorhombic space group Pnma, with a 22.063(6), b 12.106(4), c 9.745(4) Å. The Mo—P distance trans to the dinitrogen ligand (2.483(7) Å) is slightly longer than the average of the other four Mo—P bonds (2.460(5) Å). 相似文献