| 1190871-51-2

• 分子结构分类: 有机化合物 - 碳氢化合物 - 饱和烃
• CAS: 1190871-51-2
• 化学式: C₂₀H₄₄Ti
• 分子量: 336.405
• InChiKey: UVXZLTTYQONGCS-UXRWGIBNSA-N

反应信息

• 作为产物：
  描述：

  titanium(IV) tetraethanolate 、 以 not given 为溶剂， 以60%的产率得到
  参考文献：
  名称：

  Surface Organometallic Chemistry of Titanium on Silica−Alumina and Catalytic Hydrogenolysis of Waxes at Low Temperature

  摘要：

  Ti(CH(2)tBu)(4) (1) reacts selectively with the surface silanols of a silica-alumina partially dehydroxylated at 500 degrees C to provide the monosiloxy species [( SiO)Ti(CH(2)tBu)(3)](SA) (2a) and the bisiloxy Species [(=SiO)(2)Ti(CH(2)tBu)(2)](SA) (2b) in a ca. 40:60 ratio, with concomitant evolution of 1.6 +/- 0.2 equiv of neopentane per Ti. These surface complexes were characterized via the combined use of several techniques such as IR spectroscopy, H-1 MAS, C-13-CP/MAS, 2D H-1-C-13 HETCOR, and J-resolved solid-state NMR, as well as mass balance analysis. By treatment under hydrogen at 150 degrees C the neopentyl ligailds in complexes 2a,b undergo hydrogenolysis and a mixture of supported titanium species is obtained. IR, ESR, H-1 MAS, and DQ solid-state NMR spectroscopies show the presence of ca. 3% [( SiO)(M5O)TiH2](SA) (3a; M-s = Si, Al), 5% [ SiO)(MsO)Ti(Me)-H](SA) (3b), 75-80% [( SiO)(M5O)(2)Ti-H](SA) (3c), and 14% [( SiO)(MsO)(2)Ti-III](SA) (3d), along with (SiHx) and (AlHx) fragments whose formation arise from the opening of adjacent Si-O-M bridges (M = Si, Al). Species 3a-d are efficient catalysts for the hydrogenolysis of waxes with a diesel selectivity higher than 60%. Comparison with the silica-based system shows a beneficial role of the silica-alumina support on the activity of the Ti centers, attributed to a direct interaction of the surface with the active site, which possibly facilitates the beta-alkyl transfer, the key C-C bond cleavage step in the proposed mechanism.

  DOI：

  10.1021/om900151a