DFT Study of the Mechanism and Stereochemistry of the Rh(I)Catalyzed Diets-Alder Reactions between Electronically Neutral Dienes and Dienophiles

doi:10.1021/jo5017844

	DFT Study of the Mechanism and Stereochemistry of the Rh(I)Catalyzed Diets-Alder Reactions between Electronically Neutral Dienes and Dienophiles
	Liao, Wei; Yu, Zhi-Xiang
刊名	JOURNAL OF ORGANIC CHEMISTRY
	2014-12-19
卷号	79 期号:24 页码:11949-11960
ISSN号	0022-3263
DOI	10.1021/jo5017844
文献子类	Article
英文摘要	DielsAlder reaction between electronically neutral dienes and dienophiles is usually sluggish under thermal conditions and has to be catalyzed by transition metal catalysts. We report here our DFT study of the mechanism and stereochemistry of the Rh-catalyzed DielsAlder reaction between electronically neutral dienes and dienophiles (alkenes and alkynes), finding that this reaction includes a reaction sequence of oxidative cyclization between diene and alkene/alkyne and a reductive elimination step. The alkynes oxidative cyclization is much faster than alkenes due to the additional coordination of alkyne to the Rh center in the oxidative cyclization transition state. For both intermolecular and intramolecular reactions, the reductive elimination step in the catalytic cycle is rate-determining. The different reactivity of ene-diene and yne-diene substrates can be rationalized by the model that reductive elimination to form a C(sp(2))C(sp(3)) bond is easier than that for the formation of a C(sp(3))C(sp(3)) bond, due to the additional coordination of the double bond to the Rh center in the transition state in the former. We also uncovered the reasons for the high para-selectivity of the intermolecular DielsAlder reaction of dienes and alkynes. In addition, DFT calculations aiming to understand the high diastereoselectivity of an intramolecular [4 + 2] reaction of ene-dienes with substituents adjacent to the diene and ene moieties of the substrates found that the substituents in the substrates favor staying away from the Rh center in the oxidative cyclization transition states. This preference leads to the generation of the final [4 + 2] products with the substituents and the bridgehead hydrogen atoms in a cis-configuration.
WOS关键词	INTERMOLECULAR 4+2 CYCLOADDITION ; CYCLOISOMERIZATION REACTIONS ; STEPWISE MECHANISMS ; CATALYST ; ALKYNES ; VINYLCYCLOPROPANES ; COMPLEXES ; DENSITY ; STEREOSELECTION ; 1,3-BUTADIENE
WOS研究方向	Chemistry
语种	英语
出版者	AMER CHEMICAL SOC
WOS记录号	WOS:000346759500013
内容类型	期刊论文
源URL	[http://cas-ir.dicp.ac.cn/handle/321008/167306]
专题	大连化学物理研究所_中国科学院大连化学物理研究所
通讯作者	Yu, Zhi-Xiang
作者单位	Peking Univ, Coll Chem, Key Lab Bioorgan Chem & Mol Engn, BNLMS,Minist Educ, Beijing 100871, Peoples R China
推荐引用方式 GB/T 7714	Liao, Wei,Yu, Zhi-Xiang. DFT Study of the Mechanism and Stereochemistry of the Rh(I)Catalyzed Diets-Alder Reactions between Electronically Neutral Dienes and Dienophiles[J]. JOURNAL OF ORGANIC CHEMISTRY,2014,79(24):11949-11960.
APA	Liao, Wei,&Yu, Zhi-Xiang.(2014).DFT Study of the Mechanism and Stereochemistry of the Rh(I)Catalyzed Diets-Alder Reactions between Electronically Neutral Dienes and Dienophiles.JOURNAL OF ORGANIC CHEMISTRY,79(24),11949-11960.
MLA	Liao, Wei,et al."DFT Study of the Mechanism and Stereochemistry of the Rh(I)Catalyzed Diets-Alder Reactions between Electronically Neutral Dienes and Dienophiles".JOURNAL OF ORGANIC CHEMISTRY 79.24(2014):11949-11960.