将甲基三酸盐添加到 hafnocene二化合物中:逐步n(2) 甲基化和转化为一个 hafnocene 水酸盐化合物
Donald J Knobloch1, David Benito-Garagorri, Wesley H Bernskoetter
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York, 14853, USA.
Journal of the American Chemical Society
|September 30, 2009
概括
含有二联体的 hafnocene 复合物与甲基三酸盐反应,形成甲基二化物化合物. 进一步的反应产生了罕见的酸复合物,证明了二功能化的新途径.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学
背景情况:
- 丁 (N2) 是一种稳定的分子,使其激活和功能化成为化学中的一个重大挑战.
- 已知 hafnocene 和 zirconocene 复合物协调二联体,为 N2 转化提供潜在的平台.
研究的目的:
- 为了研究一个 hafnocene dinitrogen 复合体与甲基三酸盐的反应性.
- 探索在协调的二联体上形成C-N键的潜力.
- 描述所产生的甲基化产品及其随后的转化过程.
主要方法:
- 哈夫诺二复合物的合成和特征.
- 哈夫诺复合物的与甲基三酸盐的反应.
- 用光谱分析 (NMR,X射线晶体学) 来识别产品.
- 同位素标记研究以阐明反应机制.
主要成果:
- 用甲基三酸盐对哈夫诺二复合物的处理产生了一种甲基二化物哈夫诺复合物, (eta(5) -C(5) Me(4) H) ((2) Hf(OTf) (((N(2) ((CH(3))).
- 这种反应性与类似的conocene复合物形成鲜明对比,在类似的条件下它不会形成N-C键.
- 甲基二化物复合物与甲基三酸盐的进一步反应导致通过第二个N-C键的形成形成一种罕见的 hafnocene hydrazonato复合物,伴随着甲的损失.
结论:
- 甲基三酸盐可以有效地甲基化哈夫诺复合物的协调二联体,形成甲基二化物种.
- 哈夫诺甲基化复合物作为进一步功能化的前体,导致罕见的化复合物.
- 观察到的反应性突出显示了与基相似物相比,基化学中的基激活和功能化有着独特的途径.
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