纳扎罗夫循环的高效催化,使用具有相邻的性协调位点的阴离子复合物
Mesfin Janka1, Wei He, Alison J Frontier
1Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
Journal of the American Chemical Society
|June 4, 2004
概括
一种新的 ((III) 复合物有效催化纳扎罗夫循环反应. 这种催化剂通过化激活基质,从而实现有效的乙烯和乙烯基转化.
科学领域:
- 有机金属化学 有机金属化学
- 有机合成 有机合成
背景情况:
- 纳扎罗夫循环反应是合成环烯的关键反应.
- 开发纳扎罗夫循环的高效催化剂仍然是研究的一个活跃领域.
研究的目的:
- 为了研究纳扎罗夫循环化中的二化Ir (III) 复合物的催化活性.
- 阐明催化作用的机制,包括基质-催化剂复合物的形成.
主要方法:
- 合成和表征的字形化Ir (III) 复合物[IrMe (CO) (dppe) (DIB) ]2.
- 谱学研究 (例如,NMR,IR) 以检测中间物种.
- 评估催化剂在促进各种子纳扎罗夫循环的效率.
主要成果:
- 伊尔 (III) 复合体显示出高的催化活性,用于纳扎罗夫循环的aryl vinyl和divinyl 基.
- 光谱证据证实,在循环化之前形成了基质-催化剂复合体.
- 反应的效率与催化剂的电友性和通过化激活基质有关.
结论:
- 滴定性Ir(III) 复合物是纳扎罗夫循环的高效催化剂.
- 电友Ir(III) 中心对基质进行化辅助的激活,驱动了催化过程.
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