he present paper covers syntheses of the first functionalized selenacrownether, allyloxymethyl-1-selena-4, 7 , 10, 13, 16-pentaoxacyclooctadecane, and its im-mobilized product, silica-supported polypropyloxymethyl- 1-...he present paper covers syntheses of the first functionalized selenacrownether, allyloxymethyl-1-selena-4, 7 , 10, 13, 16-pentaoxacyclooctadecane, and its im-mobilized product, silica-supported polypropyloxymethyl- 1-selena-18-C- 6 siloxane.It was found that the immobilized selenacrown ether could coordinate with platinumsalt and the platinum complex was a new type of polymeric hydrosilylation catalyst.The polymer catalyst exhibited a high catalytic activity for the hydrosilylation ofolefins with triethoxysilane in the temperature range of 60 to 110℃. The turnovernumber could amount to more than 100,000 in one run.展开更多
Dibenzo-1 , 4 , 10 , 13-tetraselena-7 , 16-dioxacyclo-octadeca-2 , 11-diene was synthesized by the condensation of poly (o-diselenobenzene) with bis (2-chloroethyl) ether in the presence of potassium borohydride. The ...Dibenzo-1 , 4 , 10 , 13-tetraselena-7 , 16-dioxacyclo-octadeca-2 , 11-diene was synthesized by the condensation of poly (o-diselenobenzene) with bis (2-chloroethyl) ether in the presence of potassium borohydride. The molecular structure was examined by IR, MS and  ̄1H NMR spectra, and confirmed by an X-ray diffraction study. The molecule in the crystal has a centrosymmetry and shows a chair conformation. The dihedral angle between the plane containing the four Se atoms and the benzene ring is 104. 1 (2)°. All geometrical parameters of the molecule are unexceptional. Crystal data : C_20H_24O_2Se_4, M_r= 612. 26, monoclinic, space group P2_1/c, a=8. 866(2) , b=5. 349(1). c=22. 315(3) A, β=96. 04(2)°, V=1052. 3 A ̄3, Z=2,D_c=1.932 g/cm ̄-3 , μ(MoKα) = 69. 15 cm ̄-1, F(000) = 592, T= 297K, R= 0. 038for 1270 observed reflections and 154 refined parameters.展开更多
The preparation and X-ray crystal structures of the adducts of 10-thiabenzo-15-crown-5 and 10-selenabenzo-15-crown-5 with PdCl2 are reported. [PdCl2(C14H20O4S)2] (1): or-thorhombic, space group Pbca with cell dimensio...The preparation and X-ray crystal structures of the adducts of 10-thiabenzo-15-crown-5 and 10-selenabenzo-15-crown-5 with PdCl2 are reported. [PdCl2(C14H20O4S)2] (1): or-thorhombic, space group Pbca with cell dimensions of a=17.285(5), 6=8.354(3), c=21.689(4) A, K=3131.9 A3, Z=4;R=0.0330 for 2301 reflections with I > 3o(I), [PdCl2(C14H2oO4Se)2] (2): monoclinic, space group P21/n with cell dimensions of a=18.928(4), b=8.912(3), c=9.813(2) A, β=96.90(2)0, V=1643.4 A3, Z=2; R=0.0289 for 2617 reflections with I> 3σ(I), Both complexes are monomeric, square-planar palladiurn(Ⅱ) compounds with the Pd(Ⅱ) ion situating on a crystal-lographic inversion centre, and the crown ligands all adopt the axial coordination with the Pd-S bond of 2.3233(7) A and the Pd-Se bond of 2.4357(3) A. Their complexing characteristics are discussed in brief.展开更多
文摘he present paper covers syntheses of the first functionalized selenacrownether, allyloxymethyl-1-selena-4, 7 , 10, 13, 16-pentaoxacyclooctadecane, and its im-mobilized product, silica-supported polypropyloxymethyl- 1-selena-18-C- 6 siloxane.It was found that the immobilized selenacrown ether could coordinate with platinumsalt and the platinum complex was a new type of polymeric hydrosilylation catalyst.The polymer catalyst exhibited a high catalytic activity for the hydrosilylation ofolefins with triethoxysilane in the temperature range of 60 to 110℃. The turnovernumber could amount to more than 100,000 in one run.
文摘Dibenzo-1 , 4 , 10 , 13-tetraselena-7 , 16-dioxacyclo-octadeca-2 , 11-diene was synthesized by the condensation of poly (o-diselenobenzene) with bis (2-chloroethyl) ether in the presence of potassium borohydride. The molecular structure was examined by IR, MS and  ̄1H NMR spectra, and confirmed by an X-ray diffraction study. The molecule in the crystal has a centrosymmetry and shows a chair conformation. The dihedral angle between the plane containing the four Se atoms and the benzene ring is 104. 1 (2)°. All geometrical parameters of the molecule are unexceptional. Crystal data : C_20H_24O_2Se_4, M_r= 612. 26, monoclinic, space group P2_1/c, a=8. 866(2) , b=5. 349(1). c=22. 315(3) A, β=96. 04(2)°, V=1052. 3 A ̄3, Z=2,D_c=1.932 g/cm ̄-3 , μ(MoKα) = 69. 15 cm ̄-1, F(000) = 592, T= 297K, R= 0. 038for 1270 observed reflections and 154 refined parameters.
基金supported by the National Natural Science Foundation of China and the Doctoral Special Grant from the State Education Commission of China.
文摘The preparation and X-ray crystal structures of the adducts of 10-thiabenzo-15-crown-5 and 10-selenabenzo-15-crown-5 with PdCl2 are reported. [PdCl2(C14H20O4S)2] (1): or-thorhombic, space group Pbca with cell dimensions of a=17.285(5), 6=8.354(3), c=21.689(4) A, K=3131.9 A3, Z=4;R=0.0330 for 2301 reflections with I > 3o(I), [PdCl2(C14H2oO4Se)2] (2): monoclinic, space group P21/n with cell dimensions of a=18.928(4), b=8.912(3), c=9.813(2) A, β=96.90(2)0, V=1643.4 A3, Z=2; R=0.0289 for 2617 reflections with I> 3σ(I), Both complexes are monomeric, square-planar palladiurn(Ⅱ) compounds with the Pd(Ⅱ) ion situating on a crystal-lographic inversion centre, and the crown ligands all adopt the axial coordination with the Pd-S bond of 2.3233(7) A and the Pd-Se bond of 2.4357(3) A. Their complexing characteristics are discussed in brief.