通过可分离的双坐标Pd(0) bis-isocyanide单体的键激活,基质添加和催化
Liezel A Labios1, Matthew D Millard, Arnold L Rheingold
1Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, Mail Code 0358, La Jolla, California 92093-0358, USA.
Journal of the American Chemical Society
|July 28, 2009
概括
合成了一种新的稳定,双坐标的(0) 双异化复合物,Pd(CNAr(Dipp2)) ((2). 这种复合物在氧化加和交叉合反应中活跃,与各种基质表现出独特的反应性.
科学领域:
- 有机金属化学 有机金属化学
- 帕拉催化剂的催化方法
- 异化物复合物 异化物复合物
背景情况:
- 零价复合物在催化过程中至关重要.
- 稳定,低坐标的复合体在合成上具有挑战性.
- 异化物是协调化学中的多功能连接体.
研究的目的:
- 为了合成和表征一种新的双坐标(0) 双异化复合物.
- 为了研究这种新复合物的反应性和催化应用.
- 探索化系统的电子和结构性质.
主要方法:
- 通过金属还原合成双价位前体.
- 使用可变温度 (1)H NMR和FTIR光谱进行表征.
- 反应性研究包括氧化添加,苏子基-米亚乌拉合和与不和基质的反应.
- 使用密度函数理论 (DFT) 的计算分析.
主要成果:
- 第一个稳定的单体二坐标 (((0) 双异化物,Pd (((CNAr ((Dipp2)) 的分离.
- 证明了快速的连接体交换,没有形成三异化物.
- Pd ((CNAr ((Dipp2)) ((2)) 在氧化添加 (例如,与化,化) 和木-米亚乌拉交叉合反应中表现出活性.
- 独特的反应与三,氧 (形成过氧复合物) 和酸 (形成Pd复合物).
结论:
- Pd ((CNAr ((Dipp2)) ((2)) 是稳定的低坐标化学的重大进展.
- 复合物作为重要的有机转化过程的有效催化剂.
- 不寻常的反应性,包括与酸反应时的正式价值变化,突出显示了该复合物的独特电子性质.
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