As a result of their metal-based nucleophilicity and ability to mediate a wide range of transformations involving maingroup and carbon-based electrophiles, organometallic metallates have received considerable attention.[1] The homoleptic carbonyl metallates [Fe (CO) 4] 2À and [Co (CO) 4] À serve as the prototypical examples of this molecular class and are stabilized in part by strong π-back-bonding interactions between the highly reduced ...