Complete Switch of Selectivity in the C–H Alkenylation and Hydroarylation Catalyzed by Iridium: The Role of Directing Groups
摘要:
A complete switch in the Cp*Ir(III)-catalyzed paths between C-H olefination and hydroarylation was found to be crucially dependent on the type of directing groups. This dichotomy in product distribution was correlated to the efficiency in attaining syn-coplanarity of olefin-inserted 7-membered iridacycles. Theoretical studies support our hypothesis that the degree of flexibility of this key intermediate modulates the beta-H elimination, which ultimately affords the observed chemoselectivity.
A rhenium complex, [ReBr(CO) 3 (thf)] 2 , catalyzes the insertion of α,β-unsaturated carbonyl compounds into a C-H bond of aromatic compounds having nitrogen-containing directing groups. In this reaction, Re 2 (CO) 10 can also be used as a catalyst. When imines are employed as the aromatic substrates, sequential cyclization proceeds and indene derivatives are obtained in good to excellent yields. This
Coinage Metal (Bisfluorosulfonyl)imide Complexes: Preparation, Characterization, and Catalytic Applications
作者:Yu Tang、Biao Yu
DOI:10.1002/ejic.201901058
日期:2020.1.9
weakly coordinating counteranions in transition metal catalysis, yet their high price hinders large‐scale application. Herein, we report the preparation, characterization, and catalytic applications of silver(I), gold(I), and copper(II) (bisfluorosulfonyl)imide (–FSI) complexes, showing –FSI as a low cost alternative of –OTf and –NTf2. These complexes, including AgFSI·2MeCN (1), AgFSI·MeCN (2), AgFSI·H2O