同质的催化剂抑制了在空气中氧化酒精中的Pd黑色形成
Tetsuo Iwasawa1, Makoto Tokunaga, Yasushi Obora
1Catalysis Research Center and Division of Chemistry, Graduate School of Science, Hokkaido University, CREST, Japan Science and Technology Corporation (JST), Sapporo 001-0021, Japan.
Journal of the American Chemical Society
|May 27, 2004
概括
在同质催化过程中,新的胺连接物阻止了 (Pd) 黑色的形成. 这一突破保持了高的催化活性,用于酒精氧化,即使在高基质-催化剂比率.
科学领域:
- 催化剂是一种催化剂.
- 有机合成 有机合成
- 材料科学 材料科学 材料科学
背景情况:
- 同质催化剂,特别是 (Pd) 催化剂,遭受金属聚合和沉,导致分解和活动丧失.
- Pd黑色形成是一个常见的问题,限制了Pd催化剂在各种有机合成反应中的效率和寿命.
研究的目的:
- 开发一种新的催化剂系统,有效地抑制Pd黑色的形成.
- 为了保持高的催化活性和稳定性在有氧氧化酒精,即使在苛刻的条件下.
主要方法:
- 使用酒精的有氧氧氧化作为探针反应,探索一类新的Pd催化剂.
- 合成和应用新型化物衍生物与2,3,4,5-tetraphenylphenyl替代剂和树突单元作为Pd(OAc) 的配体2.
- 在空气下测试催化剂系统,在80°C的烯中,基质与催化剂的摩尔比率高 (S/C>1000).
主要成果:
- 这种新型的氨酸配体有效地抑制了Pd黑色的形成,即使在有氧条件下和高S/C比率下也是如此.
- 开发的催化剂系统表现出长期稳定性,并保持了高的催化活性.
- 化物和化物通过氧化酒精来产生高产量.
结论:
- 引入2,3,4,5-tetraphenylphenyl替代剂在皮里丁配体上对于抑制Pd黑色形成至关重要.
- 这种新的催化剂系统为同质的催化有氧酒精氧化提供了强大的解决方案,克服了固有的局限性.
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