Faculty Collaboration Database

Scope and mechanistic study of the ruthenium-catalyzed ortho-C-H bond activation and cyclization reactions of arylamines with terminal alkynes. J Am Chem Soc 2005 Dec 07;127(48):17000-6

Date

12/01/2005

Pubmed ID

16316246

Pubmed Central ID

PMC2585980

DOI

10.1021/ja055608s

Scopus ID

2-s2.0-28844489387 (requires institutional sign-in at Scopus site)   154 Citations

Abstract

The cationic ruthenium hydride complex [(PCy(3))(2)(CO)(CH(3)CN)(2)RuH](+)BF(4)(-) was found to be a highly effective catalyst for the C-H bond activation reaction of arylamines and terminal alkynes. The regioselective catalytic synthesis of substituted quinoline and quinoxaline derivatives was achieved from the ortho-C-H bond activation reaction of arylamines and terminal alkynes by using the catalyst Ru(3)(CO)(12)/HBF(4).OEt(2). The normal isotope effect (k(CH)/k(CD) = 2.5) was observed for the reaction of C(6)H(5)NH(2) and C(6)D(5)NH(2) with propyne. A highly negative Hammett value (rho = -4.4) was obtained from the correlation of the relative rates from a series of meta-substituted anilines, m-XC(6)H(4)NH(2), with sigma(p) in the presence of Ru(3)(CO)(12)/HBF(4).OEt(2) (3 mol % Ru, 1:3 molar ratio). The deuterium labeling studies from the reactions of both indoline and acyclic arylamines with DCCPh showed that the alkyne C-H bond activation step is reversible. The crossover experiment from the reaction of 1-(2-amino-1-phenyl)pyrrole with DCCPh and HCCC(6)H(4)-p-OMe led to preferential deuterium incorporation to the phenyl-substituted quinoline product. A mechanism involving rate-determining ortho-C-H bond activation and intramolecular C-N bond formation steps via an unsaturated cationic ruthenium acetylide complex has been proposed.

Author List

Yi CS, Yun SY

Author

Chae Yi PhD Professor, Inorganic and Organometallic Chemistry, Homogeneous Catalysis in the Chemistry department at Marquette University

MESH terms used to index this publication - Major topics in bold

Alkynes
Aniline Compounds
Catalysis
Cyclization
Kinetics
Organometallic Compounds
Quinolines
Quinoxalines
Ruthenium