When the aluminosiloxane [Ph2SiO]8[AlO(OH)]4·4Et2O (1) is reacted with propane-1,3-diamine, the coordinated ether molecules can be replaced by the nitrogen bases. Depending on the molar ratio of diamine to the aluminosiloxane, several products can be isolated with different ratios of the propanediamine (X-ray structures): [Ph2SiO]8[AlO(OH)]4·2NH2(CH2)3NH2(2) or [Ph2SiO]8[AlO(OH)]4·3NH2(CH2)3NH2(3and4). Moreover, we noticed that the adduct with three diaminopropane units exists in two different molecular structures, which are related to one another by intramolecular "switching" of hydrogen bonds. The interactions between the inorganic molecule center and the organic amine can be described as a lock-and-key model with hydrogen OH···N and NH···N bridges playing the most important role in this recognition mechanism.