| Abstract: | Abstract Tris-(trimethylsilyl)phosphane and their organo substituted derivatives (Me3Si)3?nP(Me3C)n (n: 0, 1, 2) (la-c) had been found suitable for the insertion of selenium into the phosphorus-silicon bond. At deep temperatures all silylselenophosphanes of the series (Me3SiSe)3?nP(Me3Cn) (2a-c) are formed in a nearly quantitative reaction, if no excess selenium is present. (Me3C)(Me3SiSe)2P=Se (3b) and (Me3C)2(Me3SiSe)P=Se (3c) are detectable in small quantities as the only by-products of the reaction of (Ib-c), whereas (la) end in the formation of (2a) and traces of the dimer (Me3SiSe)2P-P(SeSiMe3)2 (4). On exposure to light or at elevated temperatures (2a) undergoes a disproportionation, forming Se=P(SeSiMe3)3 (3a), and the heterocycles P3Se4(SeSiMe3) (5) and α-P4Se3(SeSiMe3)2 (6). (Me3Si)2Se is spUt off as a condensation product. After further irradiation or prolonged standing at room temperature, an insoluble oligomer is formed. The constitutions of (2-6) were determined by the analysis of their 31P- and 77Se-nmr spectra. |
