热力学研究和从罗复合物到BX3化合物的化物转移反应
Michael T Mock1, Robert G Potter, Donald M Camaioni
1Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, USA.
Journal of the American Chemical Society
|September 17, 2009
概括
过渡金属化物复合物通过化物转移促进B-H键的形成. 这项研究量化了化物供体的能力和亲和力,从而能够预测合成-化合物的有利反应.
科学领域:
- 无机化学 无机化学 有机化学
- 有机金属化学 有机金属化学
- 计算化学计算化学
背景情况:
- 过渡金属化物复合物是化学合成中的关键中间体.
- 了解化物转移对于开发新的合成方法至关重要.
- 化物和相关化合物 (BX3) 是-键的多功能前体.
研究的目的:
- 建立一种可靠的方法来预测有利的化物从过渡金属化物转移到BX3化合物.
- 量化特定过渡金属复合物和酸离子的化物供体能力.
- 为了确定各种BX3基质的化物亲和力.
主要方法:
- 实验性确定热力学化物供体能力 (ΔG°(H−)) 的HRh(dmpe) 2 和HRh(depe) 2 在乙尼中.
- 使用已建立的尺度来确定[HBEt3]−的化物捐赠能力.
- 采用计算方法 (同位体反应) 来评估BX3化合物的化物亲和力.
主要成果:
- 对于过渡金属化物化物的化物供体能力和BX3化合物的化物亲和力建立了定量尺度.
- 证明了从B-X债券中形成B-H债券是可行的.
- 展示了使用HRh{dmpe) 2减少B{\SPh) 3以产生Et3N-BH3,突出了B-X债券能量的影响.
结论:
- 该研究为涉及过渡金属化物和BX3化合物的化物转移反应提供了预测框架.
- 这些发现与氨酸和相关材料的合成有关.
- 异质 B-X 键能是决定减少程度和 B-H 键形成的关键因素.
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