Redox-Neutral Atom-Economic Rhodium-Catalyzed Coupling of Terminal Alkynes with Carboxylic Acids Toward Branched Allylic Esters
摘要:
A new method for the preparation of a wide range of branched allylic esters from terminal alkynes that proceeds via a redox-neutral propargylic CH activation employing a rhodium(I)/DPEphos catalyst is reported.
A ligand-controlled branch-selective allylic C-H carboxylation through Pd catalysis is described. The developed catalytic system, which consists of Pd(OAc)(2), sulfoxide oxazoline (sox) as a ligand and benzoquinone as an oxidant, couples terminal alkenes and carboxylic acids to furnish the corresponding branched allylic esters with high regioselectivity.