Fluorofunctional Silylamines and -Hydrazines

Fluorofunctional Silylamines and -Hydrazines -Precursors of (Si-N) Ring Systems 

Tecklenburg, U. Klingebiel Institut fur Anorganische Chemie der Universitat Gottingen, Tammannstr.4, D-37077 Gottingen, Germany 

Summary Fluorosilylamines and -hydrazines react with organolithium compounds to yield stable lithium derivatives. Perfluoro (Si-N) four- and six-membered ring systems are obtained with SiF4. The synthesis and crystal structures of the compounds are discussed. 

I) By treating bis(silylamino)difluorosilanes [1] with four equivalents of f-BuLi, thf, and [12] crown-4 lithium(lithiosilyldiamides) (1), salts with a cyclic (Li Si) anion are obtained [2]. In the reaction with two equivalents of r-BuLi, dilithiated derivatives (type 2) are formed [1-3]. 

These dilithium derivatives (2) react with SiF4 according to the substituents to give the four-membered ring systems 3 and 4 [1-3], 

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