钯（II）-二膦配合物催化的乙烯基芳烃氢胺化反应中的同位素效应以及立体和区域选择性的本质

Isotope effects and the nature of stereo- and regioselectivity in hydroaminations of vinylarenes catalyzed by palladium(ii)-diphosphine complexes.

作者信息

Vo Loan K, Singleton Daniel A

机构信息

Department of Chemistry, Texas A and M University, P.O. Box 30012, College Station, Texas 77842, USA.

出版信息

Org Lett. 2004 Jul 8;6(14):2469-72. doi: 10.1021/ol049137a.

DOI:10.1021/ol049137a

PMID:15228306

Abstract

[reaction: see text] The hydroamination of styrene with aniline catalyzed by phosphine-ligated palladium triflates exhibits a substantial (13)C isotope effect at the benzylic carbon. This supports rate-determining nucleophilic attack of amine on a eta(3)-phenethyl palladium complex. Deuterium exchange observations and predicted isotope effects based on DFT calculations support this mechanism. Selectivity in these reactions is determined by the facility of palladium displacement after reversible hydropalladation of the alkene.

摘要

[反应：见正文] 由膦配位的三氟甲磺酸钯催化的苯乙烯与苯胺的氢胺化反应在苄基碳处表现出显著的(13)C同位素效应。这支持了胺对η(3)-苯乙基钯配合物进行速率决定的亲核进攻。氘交换观察结果以及基于密度泛函理论(DFT)计算预测的同位素效应支持了这一机理。这些反应中的选择性由烯烃可逆氢化钯化后钯的取代难易程度决定。