Surface organometallic chemistry of zirconium: Chemical reactivity of the 
Si
Si
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- 作者：Adachi ; Mariko ; Né ; dez ; Christophe ; Wang ; Xu Xu ; Bayard ; Franç ; ois ; Dufaud ; Vé ; ronique ; et. al.
- 关键词：Zirconium ; Solid-state NMR ; Organometallic ; Mordenite ; Oxidation
- 刊名：Journal of Molecular Catalysis A: Chemical
- 出版年：2003
- 出版时间：September 15, 2003
- 年：2003
- 卷：204-205
- 期：Complete
- 页码：443-455
- 全文大小：462 K
文摘
The organometallic complex SiOZr(CH2C(CH3)3)3 was synthesized on the surface of silica dehydroxylated at 500°C and its reactivity towards oxygenated molecules was studied. The materials were characterized by IR, 13C CP-MAS NMR, analysis of evolved gases and elemental analysis. Reaction with neopentyl alcohol ((CH3)3CCH2OH) leads to the quantitative formation of SiOZr(OCH2C(CH3)3)3. Similarly, reaction with pivalic acid ((CH3)3CCOOH) leads to the quantitative formation of SiOZr(OCOC(CH3)3)3. Addition of dry oxygen at 25°C to SiOZr(CH2C(CH3)3)3 leads to the formation of SiOZr(OCH2C(CH3)3)3. When heated at 200°C under oxygen, the alkoxy ligands transform into carboxylate species ((CH3)3CCOO)− probably coordinated to zirconium. These results, together with molecular modelling studies of the adsorption of hydrocarbons on mordenite modified by such complexes, explain the different behaviours observed in presence of air or inert gases.
SiOZr(CH2C(CH3)3)3 was synthesized on the surface of silica dehydroxylated at 500°C and its reactivity towards oxygenated molecules was studied. The materials were characterized by IR, 13C CP-MAS NMR, analysis of evolved gases and elemental analysis. Reaction with neopentyl alcohol ((CH3)3CCH2OH) leads to the quantitative formation of SiOZr(OCH2C(CH3)3)3. Similarly, reaction with pivalic acid ((CH3)3CCOOH) leads to the quantitative formation of SiOZr(OCOC(CH3)3)3. Addition of dry oxygen at 25°C to SiOZr(CH2C(CH3)3)3 leads to the formation of SiOZr(OCH2C(CH3)3)3. When heated at 200°C under oxygen, the alkoxy ligands transform into carboxylate species ((CH3)3CCOO)− probably coordinated to zirconium. These results, together with molecular modelling studies of the adsorption of hydrocarbons on mordenite modified by such complexes, explain the different behaviours observed in presence of air or inert gases.© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |