Mechanism and Origins of Ligand-Controlled Selectivities in [Ni(NHC)]-Catalyzed Intramolecular (5+2) Cycloadditions and Homo-Ene Reactions: A Theoretical Study

被引:64
|
作者
Hong, Xin [1 ]
Liu, Peng [1 ]
Houk, K. N. [1 ]
机构
[1] Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA
基金
美国国家科学基金会;
关键词
CATALYZED INTERMOLECULAR 5+2; TRANSITION-METAL-COMPLEXES; HETEROCYCLIC CARBENE LIGANDS; DENSITY-FUNCTIONAL THEORY; OLEFIN METATHESIS; REDUCTIVE ELIMINATION; COUPLING REACTIONS; ORGANIC-CHEMISTRY; 7-MEMBERED RINGS; ALKYL BROMIDES;
D O I
10.1021/ja309873z
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
The mechanism and origins of selectivities in [Ni(NHC)]-catalyzed intramolecular (5 + 2) cycloadditions and homo-ene reactions of vinylcyclopropanes (VCPs) and alkynes have been studied using density functional theory. The preferred mechanism involves oxidative alkyne-alkene cyclization to form a metallacyclopentene intermediate, in contrast to a cyclopropane cleavage pathway in the reaction with Rh(I) catalysts. The selectivity between the (5 + 2) and homo-ene products is determined in the subsequent competing reductive elimination and beta-hydride elimination steps. Two similar-sized N-heterocyclic carbene (NHC) ligands, SIPr and ItBu, yielded reversed product selectivity, favoring the (5 + 2) and homo-ene products respectively. This is attributed to the anisotropic steric environment of these NHC ligands, which positions the bulky substituents on the ligand toward different directions and leads to distinct steric control in the reductive elimination and beta-hydride elimination transition states.
引用
收藏
页码:1456 / 1462
页数:7
相关论文
共 5 条
  • [1] Cobalt-Catalyzed Intramolecular Reactions between a Vinylcyclopropane and an Alkyne: Switchable [5+2] Cycloaddition and Homo-Ene Pathways
    Wu, Chunlin
    Yoshikai, Naohiko
    [J]. ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 2018, 57 (22) : 6558 - 6562
  • [2] Mechanism and Origins of Selectivity in Ru(II)-Catalyzed Intramolecular (5+2) Cycloadditions and Ene Reactions of Vinylcyclopropanes and Alkynes from Density Functional Theory
    Hong, Xin
    Trost, Barry M.
    Houk, K. N.
    [J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2013, 135 (17) : 6588 - 6600
  • [3] Mechanism and origins of selectivity in Ru(II)-catalyzed intramolecular (5+2) cycloadditions and ene reactions of vinylcyclopropanes and alkynes from density functional theory
    Hong, Xin
    Trost, Barry M.
    Houk, K.N.
    [J]. Trost, B.M. (bmtrost@stanford.edu), 1600, American Chemical Society (135): : 6588 - 6600
  • [4] Mechanism and Origins of Ligand-Controlled Stereoselectivity of Ni-Catalyzed Suzuki-Miyaura Coupling with Benzylic Esters: A Computational Study
    Zhang, Shuo-Qing
    Taylor, Buck L. H.
    Ji, Chong-Lei
    Gao, Yuan
    Harris, Michael R.
    Hanna, Luke E.
    Jarvo, Elizabeth R.
    Houk, K. N.
    Hong, Xin
    [J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2017, 139 (37) : 12994 - 13005
  • [5] Mechanism and origins of ligand-controlled regioselectivity of copper-catalyzed borocarbonylation of imines with B2pin2 and alkyl iodides: a computational study
    Song, Xinyi
    Wu, Hongli
    Yang, Jinjin
    Zhao, Wentao
    Huang, Genping
    [J]. ORGANIC CHEMISTRY FRONTIERS, 2023, 10 (08): : 2024 - 2032