N-SILYLATION AND SI-O BOND SPLITTING AT T HE REACTION OF LITHIATED SILOXY-SILYLAMINO-SILANES WITH CHLORO TRIMETHYLSILANE

Lithiated Siloxy-silylamino-silanes were allowed to react in tetrahydr ofurane (THF) and in n-octane (favoured) and n-hexane, resp., with chl orotrimethylsilane. The monoamide (Me(3)SiO)Me(2)Si(NLiSiMe(3)) gives in THF and in n-octane the N-substitution product (Me(3)SiO)Me(2)Si .[ N(SiMe(3))(2)] 1, the diamide (Me(3)SiO)MeSi(NLiSiMe(3))(2) only in TH F the N-substitution products (Me(3)SiO)MeSi[N(SiMe(3))(2)](2) 2 (main product) and (Me(3)SiO)MeSi[N(SiMe(3))(2)] (NHSiMe(3)) 3. In n-octane the diamide reacts mainly under Si-O bond splitting. The cyclodisilaz ane [(Me(3)SiNH)MeSi-NSiMe(3)](2) 6 is obtained as the main product. B yproducts are 2, 3 and the tris(trimethylsilylamino) substituted disil azane (Me(3)SiO)(Me(3)SiNH)MeSi-N .(SiMe(3))-SiMe(NHSiMe(3))(2) 7. The triamide (Me(3)SiO)Si .(NLiSiMe(3))(3) reacts under Si-O and Si-N bon d splitting in n-octane as well as in THF. The cyclodisilazanes [(Me(3 )SiNH)(2) . Si-NSiMe(3)](2) 10 and )RSi-N(SiMe(3))-Si(OSiMe(3))(NHSiMe (3))-N(SiMe(3)) (11: R = Me(3)SiNH, 12: R = (Me(3)Si)(2)N) are formed, in THF furthermore the N-substitution products (Me(3)SiO)Si[N(SiMe(3) )(2)]. (NHSiMe(3))(2) 4 and (Me(3)SiO)Si[N(SiMe(3))(2)](2)(NHSiMe(3)) 5. The Si-O bond splitting occurs in boiling n-octane also in absence of the chlorotrimethylsilane. An amide solution of (Me(3)SiO)MeSi(NHSi Me(3))(2) with n-butyllithium in the molar ratio 1:1 leads in n-octane and n-hexane to 6 and 7, in THF to 3. The amide solutions of (Me(3)Si O)Si .(NHSiMe(3))(3) with n-butyllithium the molar ratio 1:1 and 1:2 g ive in THF 4 and 5, respectively.