Darstellung von 1,3,5-Trimethyl-4,6-dioxo-1,3,5,2λ3-triazaphosphinanen; Einkristall-Röntgenstrukturanalyse eines Platin(II)-Komplexes/Preparation of 1,3,5-Trimethyl-4,6-dioxo-1,3,5,2λ3-triazaphosphinanes; Single Crystal X-Ray Diffraction Study of a Platinum(II)-Complex