探索与CpCr[(ArNCMe) 2CH](R) 复合物的 (III) -基键同解
K Cory MacLeod1, Julia L Conway, Brian O Patrick
1Department of Chemistry, University of British Columbia Okanagan, 3333 University Way, Kelowna, BC, Canada V1V 1V7.
Journal of the American Chemical Society
|November 13, 2010
概括
研究人员合成了对磁性(III) 单碳酸复合体,以研究R组如何影响-R键同解. R组的立体和电子因素对键强度和反应性产生影响,其中一些复合物经历同解,而另一些复合物通过光解反应.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 反应机制 反应机制
背景情况:
- 参磁性 (III) 单碳基复合物对于理解金属-碳键反应性很有意义.
- 有机配体对金属-碳键同解的不同固态和电子性质的影响尚未完全理解.
研究的目的:
- 为了合成一系列的偏磁(III) 单碳酸复合体,CpCr[(ArNCMe) 2CH](R).
- 为了研究各种R组 (初级基,基,基,基,基,基) 对Cr-R键同解的倾向的影响.
- 探索这些复合物的替代合成路径.
主要方法:
- 通过CpCr[(ArNCMe) 2CH](Cl) 的盐转化合成复合物,使用Grignard试剂或有机化合物.
- 探索使用CrII前体和激素来源的替代路线.
- 使用紫外线光谱和单晶X射线衍射进行了表征.
- 使用紫外线视光谱和与二二硫化物 (PhSSPh) 反应的Cr-R键同解的动力学研究.
主要成果:
- 紫外线光谱显示了Cr(III) -R化合物的特征波段,最大值在395-436nm和535-582nm左右.
- X射线衍射揭示了Cr-CH2R键的长度通常在2.10-2.13 Å之间,根据R组的变化 (基较长,基/基较短).
- 在室温下Cr-R键同解率与R组有显著差异;新,和异布复合物显示出可测量的同解,而其他复合物通过光解经历了干净转化为CpCr[(ArNCMe) 2CH](SPh).
结论:
- R组的固体和电子特性显著影响Cr-R键强度和同解裂裂变倾向.
- 不同的R组导致不同的反应途径,包括热同解和光化学诱导的C-S键形成.
- 这项研究提供了对金属-碳键稳定性和偏磁复合物的反应性控制因素的见解.
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