Molecular Understanding of the Formation of Surface Zirconium Hydrides upon Thermal Treatment under Hydrogen of [(SiO)Zr(CH2
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- 作者：Franck Rataboul ; Anne Baudouin ; Chloé ; Thieuleux ; Laurent Veyre ; Christophe Copé ; ret ; Jean Thivolle-Cazat ; Jean-Marie Basset ; Anne Lesage ; and Lyndon Emsley
- 刊名：Journal of the American Chemical Society
- 出版年：2004
- 出版时间：October 6, 2004
- 年：2004
- 卷：126
- 期：39
- 页码：12541 - 12550
- 全文大小：201K
- 年卷期：v.126,no.39(October 6, 2004)
- ISSN：1520-5126
文摘
The reaction of [(
SiO)Zr(CH2tBu)3] with H2 at 150 
C leads to the hydrogenolysis of thezirconium-carbon bonds to form a very reactive hydride intermediate(s), which further reacts with thesurrounding siloxane ligands present at the surface of this support to form mainly two different zirconiumhydrides: [(SiO)3Zr-H] (1a, 70-80%) and [(SiO)2ZrH2] (1b, 20-30%) along with silicon hydrides,[(SiO)3SiH] and [(SiO)2SiH2]. Their structural identities were identified by 1H DQ solid-state NMRspectroscopy as well as reactivity studies. These two species react with CO2 and N2O to give, respectively,the corresponding formate [(SiO)4-xZr(O-C(=O)H)x] (2) and hydroxide complexes [(SiO)4-xZr(OH)x](x = 1 or 2 for 3a and 3b, respectively) as major surface complexes.
SiO)Zr(CH2tBu)3] with H2 at 150 C leads to the hydrogenolysis of thezirconium-carbon bonds to form a very reactive hydride intermediate(s), which further reacts with thesurrounding siloxane ligands present at the surface of this support to form mainly two different zirconiumhydrides: [(SiO)3Zr-H] (1a, 70-80%) and [(SiO)2ZrH2] (1b, 20-30%) along with silicon hydrides,[(SiO)3SiH] and [(SiO)2SiH2]. Their structural identities were identified by 1H DQ solid-state NMRspectroscopy as well as reactivity studies. These two species react with CO2 and N2O to give, respectively,the corresponding formate [(SiO)4-xZr(O-C(=O)H)x] (2) and hydroxide complexes [(SiO)4-xZr(OH)x](x = 1 or 2 for 3a and 3b, respectively) as major surface complexes.