Advanced Synthesis & Catalysis · 2015 · 38 citations · 120 references
Natural SciencesChemistryCatalysisGreen ChemistryOrganic ChemistryCarboxylic AcidsCatalytic MechanismsOrganic AcidsOrganic SynthesisActivation Of Carboxylic Acids
Abstract A rhodium(I)‐catalyzed direct CH bond olefination of pyridyl‐substituted arenes with readily available vinyl carboxylic acids has been realized. This reaction occurred efficiently without the need for any external oxidant, affording the ortho ‐olefinated products in high yields and excellent regioselectivities. Diversely substituted vinyl carboxylic acids behaved as efficient olefination reagents under the reaction conditions, and a range of functional groups in both coupling partners was well tolerated. Mechanistic studies indicated that a decarbonylation step is involved in this catalytic process, and pivalic anhydride [( t‐ BuCO) 2 O] acts as the activator of the carboxylic acids for the in situ generation of highly active anhydrides. magnified image
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