Open AccessPalladium-Catalyzed Decarboxylative Coupling of Alkynyl Carboxylic Acids with Aryl Tosylates
Author(s) -
JuHyeon Lee,
Gabriel Charles Edwin Raja,
Subeen Yu,
Ji Min Lee,
Kwang Ho Song,
Sunwoo Lee
Publication year - 2017
Publication title -
acs omega
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.779
H-Index - 40
ISSN - 2470-1343
DOI - 10.1021/acsomega.7b01165
Subject(s) - palladium , aryl , decarboxylation , catalysis , chemistry , coupling (piping) , carboxylic acid , polymer chemistry , organic chemistry , combinatorial chemistry , materials science , alkyl , metallurgy
Decarboxylative coupling reactions of alkynyl carboxylic acids with aryl tosylates were developed in the presence of a palladium catalyst. Among the commercially available phosphine ligands, only 1-dicyclohexylphosphino-2-(di- tert -butylphosphino-ethyl)ferrocene (CyPF- t Bu) showed good reactivity. The reaction took place smoothly and gave the decarboxylative coupled products in moderate to good yields. This demonstrates the excellent functional group tolerance toward alkyl, alkoxy, fluoro, thiophenyl, ester, and ketone groups. In addition, alkyl-substituted propiolic acids, such as octynoic and hexynoic acids, were coupled with phenyl tosylate to provide the desired products. We found that the electronic properties of the substituents on the phenyl ring in arylpropiolic acids are an important factor. The order of reactivity was found to be aryl iodide > aryl bromide > aryl tosylate > aryl chloride. However, aryl chloride-bearing electron-withdrawing groups showed higher reactivity than those bearing aryl tosylates.