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• 作者：Marta Abrantes ; Tatiana R. Amarante ; Margarida M. Antunes ; Sandra Gago ; Filipe A. Almeida Paz ; Irene Margiolaki ; Alrio E. Rodrigues ; Martyn Pillinger ; Anabela A. Valente ; Isabel S. Gonalves
• 刊名：Inorganic Chemistry
• 出版年：2010
• 出版时间：August 2, 2010
• 年：2010
• 卷：49
• 期：15
• 页码：6865-6873
• 全文大小：944K
• 年卷期：v.49,no.15(August 2, 2010)
• ISSN：1520-510X

文摘

The reaction of [MoO₂Cl₂(bipy)] (1) (bipy = 2,2′-bipyridine) with water in a Teflon-lined stainless steel autoclave (100 °C, 19 h), in an open reflux system with oil bath heating (12 h) or in a microwave synthesis system (120 °C, 4 h), gave the molybdenum oxide/bipyridine hybrid material {[MoO₃(bipy)][MoO₃(H₂O)]}_n (2) as a microcrystalline powder in yields of 72−92%. The crystal structure of 2 determined from synchrotron X-ray powder diffraction data is composed of two distinct neutral one-dimensional polymers: an organic−inorganic polymer, [MoO₃(bipy)]_n, and a purely inorganic chain, [MoO₃(H₂O)]_n, which are interconnected by O−H···O hydrogen bonding interactions. Compound 2 is a moderately active, stable, and selective catalyst for the epoxidation of cis-cyclooctene at 55 °C with tert-butylhydroperoxide (tBuOOH, 5.5 M in decane or 70% aqueous) as the oxidant. Biphasic solid−liquid or triphasic solid−organic−aqueous mixtures are formed, and 1,2-epoxycyclooctane is the only reaction product. When n-hexane is employed as a cosolvent and tBuOOH(decane) is the oxidant, the catalytic reaction is heterogeneous in nature, and the solid catalyst can be recycled and reused without a loss of activity. For comparison, the catalytic performance of the precursor 1 was also investigated. The IR spectra of solids recovered after catalysis indicate that 1 transforms into the organic−inorganic polymer [MoO₃(bipy)] when the oxidant is tBuOOH(decane) and compound 2 when the oxidant is 70% aqueous tBuOOH.