机械洞察力催化h(2) 氧化由含有diphosphine连接体与定位氨基基基的ni复合体
Jenny Y Yang1, R Morris Bullock, Wendy J Shaw
1Chemical and Materials Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
Journal of the American Chemical Society
|April 4, 2009
概括
一个新的复合物,Ni (dppp) P (ph) N (bz) BF (4)) 2催化了H (2) 的氧化. 低温核磁共振检测显示了H(2) 激活中的中间体,显示了和悬挂基之间的质子交换.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 协调化学 协调化学
背景情况:
- 尼克尔复合物与二素联体被研究用于催化应用.
- 了解激活机制对于开发高效的催化剂至关重要.
- 悬浮基在稳定反应性中间体中的作用具有重大意义.
研究的目的:
- 为了合成和表征一种新型的混合联体复合物,[Ni(dppp) (((P(Ph) ((2) N(Bz) ((2)) ] ((BF ((4)) ((2)).
- 研究由该复合体催化的激活和电化学氧化机制.
- 为了阐明悬挂原子在H(2) 裂变期间在二氨酸连接体中的作用.
主要方法:
- 目标复合物的合成.
- 单晶X射线衍射用于结构性确定Ni(0) 衍生物.
- 低温核磁共振 (NMR) 光谱法用于识别反应中间体.
- 电化学研究,以评估H(2) 氧化的催化活性.
主要成果:
- 混合联体复合物[Ni ((dppp)) ((P ((Ph)) ((2) N ((Bz)) ((2))) ((BF ((4))) ((2)) 已成功合成.
- 观察到H(2) 的异质裂变,形成一个化物种,在二素联体的原子上与质子相互作用.
- 确定了两个不同的中间体,一种二化物和一种质子联体物种,并表明它们通过可逆质子交换相互转换.
- 该复合体在基存在的情况下,对电化学H(2) 氧化具有催化活性.
结论:
- 在Ni (II) 复合体中存在定位悬挂基,显著有利于H (II) 激活.
- 低温核磁共振对催化循环期间的动态质子交换机制提供了宝贵的见解.
- 这项研究有助于理解与催化相关的激活通路.
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