Studying Regioisomer Formation in the Pd-Catalyzed Fluorination of Cyclic Vinyl Triflates: Evidence for in situ Ligand Modification

被引：2

作者：

Ye, Yuxuan ^{[1
]}

Kim, Seoung-Tae ^{[2
,3
]}

King, Ryan P. ^{[1
]}

Baik, Mu-Hyun ^{[2
,3
]}

Buchwald, Stephen L. ^{[1
]}

机构：

[1] MIT, Dept Chem, Cambridge, MA 02139 USA

[2] Korea Adv Inst Sci & Technol KAIST, Dept Chem, Daejeon 34141, South Korea

[3] Inst Basic Sci IBS, Ctr Catalyt Hydrocarbon Functionalizat, Daejeon 34141, South Korea

来源：

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION | 2023年 / 62卷 / 15期

基金：

美国国家卫生研究院;

关键词：

Dearomatization; Density-Functional Calculations; Fluorination; Palladium; Reaction Mechanism; EFFECTIVE CORE POTENTIALS; F REDUCTIVE ELIMINATION; MOLECULAR CALCULATIONS; DIPEPTIDE ISOSTERES; PALLADIUM; CHEMISTRY; TRIFLUOROMETHYLATION; PHARMACEUTICALS; (Z)-ALKENE; CONVERSION;

D O I：

10.1002/anie.202300109

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Pd-catalyzed nucleophilic fluorination reactions are important methods for the synthesis of fluoroarenes and fluoroalkenes. However, these reactions can generate a mixture of regioisomeric products that are often difficult to separate. While investigating the Pd-catalyzed fluorination of cyclic vinyl triflates, we observed that the addition of a substoichiometric quantity of TESCF3 significantly improved the regioselectivity of the reaction. Herein, we report a combined experimental and computational study on the mechanism of this transformation focusing on the role of TESCF3. The poor regioselectivity of the reaction in the absence of additives results from the formation of LPd-cyclohexyne complexes (L=biaryl monophosphine ligand). When TESCF3 is added to the reaction mixture, the generation of the Pd-cyclohexyne complexes is diminished by an unexpected pathway involving the dearomatization of the ligand by nucleophilic attack from a trifluoromethyl anion (CF3-).

引用

页数：9