General Reaction Mode of Hypervalent Iodine Trifluoromethylation Reagent: A Density Functional Theory Study

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	General Reaction Mode of Hypervalent Iodine Trifluoromethylation Reagent: A Density Functional Theory Study
	Ling L(凌琳)1; Liu K(刘鲲)1; Li XQ(李鑫倩)1; Li YX(李玉学)1
刊名	ACS Catal.
	2015
卷号	5 期号:4 页码:2458-2468
其他题名	高碘三氟甲基化试剂 (Togni 试剂1)反应模式的理论研究
通讯作者	李玉学
英文摘要	The mechanisms of trifluoromethylation with hypervalent iodine trifluoromethylation reagent (Togni's reagent 1) have been comprehensively studied by density functional theory (DFT) calculations. The results show that there are two general reaction modes for reagent 1: (I) Mode-A, acting as a CF3 center dot free radical source. When one-electron reductants are available in the reaction system, such as Cu-I, Fe-II TEMPONa, or electron-rich lithium enolate, 1 will be reduced via single-electron transfer (SET) and give out CF3 center dot free radical concertedly. In the Cu-I-catalyzed trifluoromethylation of terminal olefins, Cu-I promotes the homo-cleavage of the F3C-I bond in 1 via SET to produce Cull species and CF3 center dot free radical. Then the CF3 center dot free radical attacks the olefin, leading to trifluoromethyl alkyl radical intermediate. Subsequently, the Cull species act as a one-electron oxidant oxidizing the alkyl radical to carbocation intermediate, and the following deprotonation leads to the final product. Other mechanisms, such as formation of F3C-Cu-III species via oxidative addition, formation of allylic radical intermediate, were considered and excluded. (II) Mode-B, acting as a CF3+ cation source. 1 can be activated by a Lewis acid such as Zn-II and becomes more inclined to undergo an S(N)2 type nudeophilic attack at the CF3 group by nucleophiles (pentanol in this work). For substrates studied in this paper, such as the lithium enolate, pentanol, and sodium 2,4,6-trimethylphenolate, the competition between their reducibility and nudeophilicity determines the reaction mode of regent 1.
学科主题	金属有机化学
收录类别	SCI
原文出处	http://dx.doi.org/10.1021/cs501892s
语种	英语
WOS记录号	WOS:000352464400051
内容类型	期刊论文
源URL	[http://ir.sioc.ac.cn/handle/331003/39590]
专题	上海有机化学研究所_金属有机化学国家重点实验室
作者单位	1.中科院上海有机化学研究所, 金属有机化学国家重点实验室 2.天津师范大学
推荐引用方式 GB/T 7714	Ling L,Liu K,Li XQ,et al. General Reaction Mode of Hypervalent Iodine Trifluoromethylation Reagent: A Density Functional Theory Study[J]. ACS Catal.,2015,5(4):2458-2468.
APA	凌琳,刘鲲,李鑫倩,&李玉学.(2015).General Reaction Mode of Hypervalent Iodine Trifluoromethylation Reagent: A Density Functional Theory Study.ACS Catal.,5(4),2458-2468.
MLA	凌琳,et al."General Reaction Mode of Hypervalent Iodine Trifluoromethylation Reagent: A Density Functional Theory Study".ACS Catal. 5.4(2015):2458-2468.