| Abstract: | Fluorosilyl and Fluoroboryl Substituted Cyclotetrasilazanes. Synthesis and Crystal Structures Mono- and dilithiated octamethylcyclotetrasilazanes ( 1, 6 ) react with fluorosilanes and F2BN(SiMe3)2, respectively, under retention of the cyclotetrasilazane structure yielding the mono- and disubstituted compounds 2–5 and 7–13 . In the reaction of the dilithium compound 6 with a fluorsilane in equivalent amounts, the bicyclic compounds 14 and 15 are obtained. Crystallographic investigations of the compounds 2, 3, 8 , and 9 indicate that the monosilylated eight-membered ring has a cradle conformation while the disilylated ring has a chair conformation. The X-ray structure of the bicyclic system 14 indicates that the nitrogen atoms of the Si3N-units have a pyramidal environment. |
