TRISILAZAN-1-YL-CYCLODISILAZANES - EXPANSIONS, CONTRACTIONS, AND RING COUPLINGS

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 F2BN(SiMe3)2. An analogous silylbridged four‐membered ring system 12 is formed in the reaction of the eight‐membered ring anion with F3SiN(SiMe3)2. Copyright © 1990 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim