The Zr-C bond chemistry and, particularly, its migration properties have been investigated where the metal is bonded to the dibenzotetramethyltetraaza[14]annulene (tmtaa) dianion in the model complexes cis-[Zr(tmtaa)R(2)]. In this respect the [Zr(tmtaa)] fragment has been analyzed in comparison with the well-known [cp(2)Zr] moiety, with the support of an extended Huckel analysis. The synthesis of [Zr(tmtaa)R(2)] (R = Me, 2; R = CH(2)Ph, 3) from [Zr(tmtaa)Cl-2] (1) has been achieved under highly controlled reaction conditions.