Trisilazan‐1‐yl‐cyclodisilazane — Expansionen, Kontraktionen und Ringkopplungen

Trisilazan‐1‐yl‐cyclodisilazanes — Expansions, Contractions. and Ring Couplings Lithiated trisilazan‐1‐yl‐cyclodisilazanes react in different ways. The lithium derivatives of 2 and 3 react with fluorosilanes with substitution to give 4 and 5 . In the reaction of dilithiated 3 with chlorotrimethylsilane the cyclotrisilazane 6 is formed by ring expansion. In the same reaction the symmetrically substituted four‐membered ring 7 is obtained, which is formed by ring contraction of the anion of 6 . The silyl‐bridged ring systems 8 – 11 are obtained on reaction of dilithiated 3 with fluorosilanes and F 2 BN(SiMe 3 ) 2 . An analogous silylbridged four‐membered ring system 12 is formed in the reaction of the eight‐membered ring anion with F 3 SiN(SiMe 3 ) 2 .