The reaction of (Et3P)2PtGe[N(SiMe3)2]2 with dioxygen yields (Et3P)2Pt(μ-η2-O 2)Ge[N(SiMe3)2]2 (1). Exposure of 1 to light resulted in a rearrangement to (Et3P)2PtO2Ge[N(SiMe3) 2]2 (2a), the first example of a bidentate, dianionic germanate ligand. The isomerization was judged to occur via an intramolecular O-O bond scission and rotation of the Pt-Ge bond. No free germylene was detected, and the reaction was found to be zero order. An analogue of 2a was prepared by direct reaction of (Ph3P)2PtO2 with Ge[N(SiMe3)2]2 yielding (Ph3P)2PtO2-Ge[N(SiMe3) 2]2 (2b). Addition of SO2 to 1 results in the formation of the bridging sulfate (Et3P)2Pt(μ-η2-SO 4)-Ge[N(SiMe3)2]2 (3). An infrared spectroscopy study of the sulfate reaction was performed using oxygen-18. The results indicate that direct insertion of SO2 into the O-O bond does not occur. Formaldehyde was also observed to insert into the Pt-O bond of 1 giving (Et3P)2Pt(μ-η2-OCH 2OO)Ge[N(SiMe3)2]2 (5).