In the case of [Me 4 N] [AlCl 4 ], only the AlX/CUBE = 1.5 stoichiometry was used to avoid too heavily cross-linked products. To our surprise, a full condensation, as monitored by the evolved SnMe3Cl, was not reached and SnMe4 was also generated. Further analysis revealed that the total average connectivity on Al reached 4 (3.98), pointing at the existence of a competing mechanism of condensation where the Cl atom remains embedded in the material and SnMe4 is evolved instead.