Mu‐nick: The methyl iodide‐mediated ring opening of nickelalactones, which can be formed by oxidative coupling of carbon dioxide and ethylene at Ni0 complexes, induces β‐H elimination, producing methyl acrylate in yields of up to 56 %. This reaction is found to be very sensitive to the ligands coordinated to the central nickel atom.

Ring opening of various nickela-and palladalactones induced by the cleavage of the M-O bond by methyl trifluoromethanesulfonate (MeOTf) and methyl iodide (MeI) is examined. Experimental evidence supports the mechanism of ring opening by the alkylating agent followed by b-H elimination leading to methyl acrylate and a metal-hydride species. MeOTf shows by far higher efficiency in the lactone ring opening than any other methylating agent including the previously reported methyl iodide.