Two attempts to módify the ammonium salts of silyl thiol and silyl
selenol were made in an effort to make them easily soluble. Both
attempts were unsuccessful. The first was to try to form the potassium
salt by using an ion exchange resin; the second was to prepare the
methylsilyl derivative in the hope that it would be soluble. The
ammonium salt of silyl tellurol was also prepared by an analogous route
to the sulphur and selenium compounds.2H₂Te + (SiH₃)₃N → NH₄TeSiH₃ + (SiH3)₃Te ¹.Methyl silyl telluride was prepared from it by adding methyl iodide.CH₃I + NH₄ TeSiH₃ → CH₃TeSiH₃ + NH₄ I ².Lithium silyl oxide, sulphide and selenide was prepared by the
reaction of methyl lithium, as a solution in diethyl ether at -64°,
with disiloxane, disilyl sulphide and disilyl selenide.CH₃Li + (SiH₃)₂Y → LiYSiH₃ + CH₃SiH₃ ³.Y = (0, S, Se)Similar reactions were carried out with methyl lithium and trisilyl
phosphine and trisilyl arsine.CH₃Li + (SiH₃)₃Z→LiZ(SiH₃)₂ + CH₃SiH₃'⁴Z= (P, As)Yields of the lithium derivatives were all of the order of 80% and
they were characterised by i.r., raman and n.m.r. spectroscopy. In
some cases a reaction with trimethylsilyl chloride was also carried out.Reactions of these compounds, as a solution in diethyl ether, were
carried out with a variety of reagents but most were unsuccessful in
that the desired products were not isolated. Instead, the main
volatile silyl product was generally (SiH₃)₃Z or (SiH₃)₂Y. This
was attributed to the side-reactions:SiH₃ - Y - Q +Bθ → SiH₃B + θY - Q ⁵.and (SiH₃)₂Z - Q + Bθ → SiH₃B + SiH₃QZθ ⁶.where Q is any group of interestand Bθ is a base - in this case YSiH₃ or Z(SiH₃)₂This conclusion was confirmed by reactions of the silyl anions and
closely related molecules producing exchange situations. Attempts
to limit the extent of reactions (5) and (6) consisted of the use of
benzene as a solvent, the use of trimethylamine and the absence of
solvent. The first two were unsuccessful but the latter worked.
It was possible to prepare disilyl phosphine and 1,1,1-trimethyl
disiloxane by this method.2LiP(SiH₃)₂ + H₂S -- HP(SiH₃)₂ + Li₂S ⁷.Li0SiH₃ + (CH₃)₃SiCl → (CH₃)₃0SiH₃ + LiCl ⁸