Tetramethyl-N,N′-bis-o-tolylcyclodisilazane was prepared in order to study the effect of o-substitution of the N-phenyl ring on the molecular structure. A crystal structure determination was carried out together with UV, 1H NMR and MS spectroscopic investigations. The o-tolyl group forms a dihedral angle of -89.6° with the cyclodisilazane ring. This conformation is completely different from that in the two coplanar N-phenyl derivatives previously studied. The molecular geometry and spectroscopic data suggest decreased delocalization, in agreement with the low thermal stability. While the geometry of the cyclodisilazane moiety is unchanged, mass spectroscopic fragmentation indicates that the SiN bonds are weaker than those in N-phenyl derivatives containing phenyl groups coplanar with the four-membered ring.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry
- Materials Chemistry