Computational Mechanistic Study of Redox-Neutral Rh(III)-Catalyzed C-H Activation Reactions of Arylnitrones with Alkynes: Role of Noncovalent Interactions in Controlling Selectivity

作者：Xing Yang Yang; Liu Jian Biao; Tian Ying Ying; Sun Chuan Zhi; Huang Fang; Chen De Zhan

来源：Journal of Physical Chemistry A, 2016, 120(46): 9151-9158.

DOI：10.1021/acs.jpoca.6610367

The mechanism of redox-neutral Rh(III)-catalyzed coupling reactions of arylnitrones with alkynes was investigated by density functional theory (DFT) calculations. The free energy profiles associated with the catalytic cycle, involving C(sp(2))-H activation, insertion of alkyne, transfer of O atom, cyclization and protodemetalation, are presented and analyzed. An overwhelming preference for alkyne insertion into Rh-C over Rh-O is observed among all pathways, and the most favorable route is determined. The pivalate-assisted C-H activation step is turnover-limiting, and the cyclization step determines the diastereoselectivity of the reaction, with the stereoselectivity arising mainly from the difference of noncovalent interactions in key transition states. The detailed mechanism of O atom transfer, Rh-III-Rh-I-Rh-III versus Rh-III-Rh-V-Rh-III cycle, is discussed.

• 出版日期2016-11-24
• 单位山东师范大学