MISCELLANEOUS REACTIONS OF SOME TRIS(TRIMETHYLSILYL)METHYLSILICON COMPOUNDS

TsiSiMe2I (Tsi = (Me3Si)3C) gives TsiSiMe2OMe on treatment with AgBF4 in MeOH but some TsiSiMe2F if an excess of CsF is also present. The triflates TsiSiMe2OSO2CF3 and (Me3Si)2C(SiMePh2(SiMe2OSO2CF3) react with alkali metal salts MX to give the corresponding derivatives TsiSiMe2X and (Me3Si)2C(SiMePh2)(SiMe2X). TsiSiMe2OSO2CF3 does not react with CF3CH2OH. The relative rates of reaction of the halides TsiSiMe2X with X = Cl, Br or I with KSCN in boiling MeCN are roughly 1/2.5/6, revealing a suprisingly little variation in reactivity among the halides. TsiSiPh2I and TsiSiMePhI undergo hydrolysis in MeCn or Me2SO to give TsiSiPh2OH and TsiSiMePhOH, the absence of rearrangement showing that cationic intermediates are not involved. TsiSiPh2I reacts slowly with KSCN in MeCN to give TsiSiPh2NCS. TsiSiPh2H reacts with IBr to give the rearranged bromide (Me3Si)2C(SiMePh2)(SiMe2Br). Under UV irradiation: (i) TsiSiPh2I in 1-bromohexane gives the rearranged bromide (Me3Si)2C(SiMePh2)(SiMe2Br); (ii) TsiSiMe2N3 in MeOH undergoes solvolysis; (iii) tBu3SiI in CCl4 gives tBu3SiCl and Cl3CCCl3, and in MeOH undergoes photocatalysed methanolysis. © 1990.