Insertion reactions of α,ω-bis-carbodiimides (RNCN)₂X (1–5: R = Et, t-Bu, Ph; X = C₃H₆, C₄H₈) with 2 equiv of AlMe₃ yielded the dinuclear tethered bis-amidinate–alane complexes [RNC(Me)NAlMe₂]₂X (R = Et, X = C₄H₈ (6); R = t-Bu, X = C₃H₆ (7), C₄H₈ (8)). Analogous reactions with 4 equiv of AlMe₃ resulted in the coordination of two additional AlMe₃ molecules, yielding the tetranuclear bis-amidinate complexes [EtN(AlMe₃)C(Me)NAlMe₂]₂X (X = C₃H₆ (9), C₄H₈ (10)) and [t-BuNC(Me)N(AlMe₃)AlMe₂]₂X (X = C₃H₆ (11), C₄H₈ (12)). In addition, equimolar reactions between (RNCN)₂X (R = Et, X = C₃H₆, C₄H₈; R = Ph, X = C₄H₈) and 2 equiv of AlMe₃ at elevated temperatures occurred with intramolecular cyclization and formation of [EtNC(Me)NC₃H₆N(AlMe₃)CNEt]AlMe₂ (13) and [RNC(Me)NC₄H₈N(AlMe₃)CNR]AlMe₂ (R = Et (14), Ph (15)). Hydrolysis of 11 gave the protonated free ligand PhNC(Me)NC₄H₈N(H)CNPh (16) in high yield. 6–16 were characterized by elemental analyses, multinuclear NMR (¹H, ¹³C) and IR spectroscopy, and single-crystal X-ray diffraction (7, 10–14, 16).