Trimethylsilyl iodide may be prepared by the oxidative cleavage of hexamethyldisilane by iodine or by the cleavage of hexamethyldisiloxane with aluminium triiodide.
: TMS-TMS + I → 2 TMSI (TMS = (CH)Si)
: 3 TMS-O-TMS + 2 AlI → 6 TMSI + AlO