The allyl ligand is commonly found in organometallic chemistry. Most commonly, allyl ligands bind to metals via all three carbon atoms, the η-binding mode.  The η-allyl group is classified as an LX-type ligand in the Green LXZ ligand classification scheme, serving as a 3e donor using neutral electron counting and 4e donor using ionic electron counting.  More common are complexes with allyl and other ligands.  Examples include (η-allyl)Mn(CO) and CpPd(allyl).