铁催化脱水合/脱氨酸-酸的氨酸-酸
James R Vance1, André Schäfer, Alasdair P M Robertson
1School of Chemistry, University of Bristol, Cantock's Close , Bristol BS8 1TS, U.K.
Journal of the American Chemical Society
|February 18, 2014
概括
铁碳基复合物有效地催化了氨基脱水连接到循环二甲. 对铁前催化剂1和2观察到不同的机制,纳米粒子形成影响了催化活性.
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.
- 材料科学 材料科学 材料科学
背景情况:
- 铁碳化合物复合物是易于获得的多功能预催化剂.
- 氨基烯是材料合成的重要前体.
- 脱水合反应为有价值的循环化合物提供了一条途径.
研究的目的:
- 为了研究铁碳基复合物的有效性,作为氨基-脱水合的前催化剂.
- 阐明触媒循环中涉及的机械路径.
- 探索活性催化物种的性质,均或异质.
主要方法:
- 用铁碳烯预催化剂对氨基进行紫外线光辐射.
- 在现场11BNMR光谱用于反应监测.
- 实验和计算DFT研究用于机械研究.
主要成果:
- 铁碳基复合物[CpFe(CO) ]2 (1) 和CpFe(CO) 2I (2) 从Me2NH·BH3 (3) 有效地产生了循环二博拉[Me2N-BH2]2 (4) .
- 对于前催化剂1和2,确定了不同的两步机制,涉及不同的中间体.
- 一个更活跃的催化剂,Cp2Fe2(CO) 3(MeCN) (7),形成铁纳米粒子 (异质) 并不需要光激活.
- 前催化剂2产生了同质的活性催化剂,而前催化剂1可能在光辐射下形成异质的纳米粒子.
结论:
- 铁碳基复合物作为氨基脱水合的有效前催化剂.
- 催化机制和活性物种的性质 (同质与异质) 取决于特定的铁前催化剂.
- 铁纳米粒子的形成可以显著增强这些脱水合反应中的催化活性.
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