• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Chemistry: A European journal >Aerobic epoxidation of olefins catalyzed by the cobalt-based metal-organic framework STA-12(Co)
【24h】

Aerobic epoxidation of olefins catalyzed by the cobalt-based metal-organic framework STA-12(Co)

机译：钴基金属有机骨架STA-12（Co）催化的烯烃的好氧环氧化

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

A Co-based metal-organic framework (MOF) was investigated as a catalytic material in the aerobic epoxidation of olefins in DMF and exhibited, based on catalyst mass, a remarkably high catalytic activity compared with the Co-doped zeolite catalysts that are typically used in this reaction. The structure of STA-12(Co) is similar to that of STA-12(Ni), as shown by XRD Rietveld refinement and is stable up to 270 °C. For the epoxidation reaction, significantly different selectivities were obtained depending on the substrate. Although styrene was epoxidized with low selectivity due to oligomerization, (E)-stilbene was converted with high selectivities between 80 and 90%. Leaching of Co was low and the reaction was found to proceed mainly heterogeneously. The catalyst was reusable with only a small loss of activity. The catalytic epoxidation of stilbene with the MOF featured an induction period, which was, interestingly, considerably reduced by styrene/stilbene co-epoxidation. This could be traced back to the formation of benzaldehyde promoting the reaction. Detailed parameter and catalytic studies, including in situ EPR and EXAFS spectroscopy, were performed to obtain an initial insight into the reaction mechanism. Aim for the STAs: The metal-organic framework catalyst STA-12(Co) showed remarkable activity in the aerobic epoxidation of E-stilbene in DMF (see figure) and could be efficiently recycled. High selectivity (80-90%) for stilbene oxide was observed. The induction period of the reaction could be reduced by styrene/stilbene co-epoxidation. Detailed parameter studies combined with spectroscopic investigations were performed to obtain an initial insight into the reaction mechanism.
机译：研究了钴基金属有机骨架（MOF）作为DMF中烯烃有氧环氧化的催化材料，并且基于催化剂质量，与通常使用的钴掺杂沸石催化剂相比，其具有非常高的催化活性在这个反应中。 XRD Rietveld精炼显示，STA-12（Co）的结构与STA-12（Ni）相似，并且在270°C的温度下稳定。对于环氧化反应，根据底物获得明显不同的选择性。尽管由于低聚，苯乙烯以低选择性被环氧化，但是（E）-二苯乙烯以80-90％之间的高选择性被转化。 Co的浸出量低，并且发现该反应主要以非均相进行。该催化剂可重复使用，而活性损失很小。用MOF催化二苯乙烯的催化环氧化具有一个诱导期，有趣的是，苯乙烯/二苯乙烯共环氧化大大降低了诱导期。这可以追溯到促进反应的苯甲醛的形成。进行了详细的参数和催化研究，包括原位EPR和EXAFS光谱学，以初步了解反应机理。 STA的目标：金属有机骨架催化剂STA-12（Co）在DMF中的E-二苯乙烯的好氧环氧化中显示出显着的活性（见图），可以有效地回收利用。观察到对氧化二苯乙烯的高选择性（80-90％）。反应的诱导期可以通过苯乙烯/苯乙烯共环氧化来缩短。详细的参数研究与光谱学研究相结合，以获得对反应机理的初步了解。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号