Monoethoxydimetylchlorosilane was synthesized by the alcoholysis reaction of dimethyldichlorosilane and ethanol in the liquid-gas system.Then in the presence of FeCl3 as a catalyst

the intermediate dichlorotetramethyldisiloxane was prepared by refluxing monoethoxydimetylchlorosilane.Finally

1

1

3

3-tetramethyldisiloxane was obtained by reducing the intermediate in anhydrous ether using CaH2 as reducer.The factors influencing their yields were also discussed and its structure was also characterized by elemental analysis

IR

and 1HNMR.Compared with other methods

the raw materials is amazedly cheaper and the process is more convenient

lower cost

higher yields（86%）

and more satisfied industrialization.