The hydride ligands of 1 -though essential for the stability of these complexes -are non-nucleophilic and non-basic. The dyotropic rearrangement leads to the establishment of a terminal Al-H bond in 2a which exposes new reactivity previously not observed with the parent complex 1. This has been demonstrated by further experiments in which 1 and 2a were reacted with various electrophiles (Scheme 4).