Methyliodine exchange in (η 5-iodocyclopentadienyl)metallo methyl derivatives of iron(II), tungsten(II), and molybdenum(II) in the presence of palladium

Abstract

A new and unexpected interchange reaction has been discovered during an attempt to make fulvalene-linked heterobimetallic complexes by palladium-catalyzed coupling between η 5-(iodo)cyclopentadienyl and η 5(trimethyltin)cyclopentadienyl metal complexes. In the presence of Pd the (η 5-iodocyclopentadienyl)metallo methyl derivatives of general formula (η 5-IC 5H 4)M(CO) n CH 3 (M = Fe, n = 2; M = W, n = 3; M = Mo, n = 3) undergo methyl-iodine exchange, to give the corresponding (η 5-CH 3C 5H 4)M(CO) n I complexes. The palladium(0) catalysis of the reaction apparently involves an intramolecular transmetallation.