The condensation reaction between Ph2Si(OC(O)CH3)2 and OP(OSiMe3)3 leads to elimination of CH3C(O)OSiMe3 and the formation of the new silicophosphate cage molecule Ph12Si6P4O16 (1) with an adamantane-like core possessing four terminal P═O moieties and six O-SiPh2-O bridging groups. Compound 1 was further reacted with the Lewis acid B(C6F5)3. We observed adduct formation by coordination through the P═O→B bonds and isolated and structurally characterized two new molecules. In the first of them, the adamantane-like cage is preserved and three phosphoryl oxygen atoms coordinate to boranes, forming Ph12Si6O16P4·3B(C6F5)3 (2); the remaining P═O group is inverted toward the cage center pointing along a C3 molecular axis. The molecule is chiral, and the compound 2 crystallizes as a conglomerate of homochiral crystals. Enantiomers 2M and 2P were both structurally characterized. The second adduct resulted from an unexpected reorganization of the Si-O-P linkages in the adamantane cage during the reaction of 1 with 4 equiv of B(C6F5)3. The bis-adduct Ph6Si3O8P2·2B(C6F5)3 (3) was formed with an inorganic core representing half of the parent molecule 1.