Chloro(chloromethyl)dimethylsilane

Chloro(chloromethyl)dimethylsilane is an important intermediate for Alfa-series silane coupling agents, also can be used for synthesis of pesticides.

Clear to straw liquid

Chloro(chloromethyl)dimethylsilane is used in method of improving the hydrophobic properties of cellulosic materials without leaving an acidic residue.

At room temperature, 0.21 g (1.6 mmol) of anhydrous aluminum chloride was added to a stirred solution of 2.34 g (16 mmol) of 1a and 20 mL of dry hexane in a 50 mL two-necked round-bottomed flask equipped with a reflux condenser and inlet tube. The mixture was stirred for 20 min at room temperature and the solution was quenched with 1.22 g (8 mmol) of phosphorus trichloride. The POCl3-AlCl3 complex salt was removed by filtration. The filtrate was distilled under vacuum ball by ball. Distillation of the mixture under vacuum gave 3-butenylchlorodimethylsilane 2a (1.75 g, bp 128-130C) in 75% yield. Other by-products were also obtained by vacuum distillation, identified as chloromethylchlorodimethylsilane (12%) and unidentified high boiling polymeric materials (10%). Using the reaction procedure described above, 1a (1.0 g, 6.7 mmol) was reacted with allyltrimethylsilane (2.26 g, 20.0 mmol) in the presence of aluminum chloride (0.09 g, 0.67 mmol) for 2.5 h at room temperature to give 1,1-dimethyl-3-(2-trimethylsilylmethyl-4-pentenyl)silyl chloride pentane (4, 0.72 g, 40%) , 2a (0.18 g) and 3a, (12%). The two diastereomeric components were separated by column chromatography on alumina (3.0 x 100.0 cm) using n-hexane eluent to obtain the main product chloromethyl dimethyl chlorosilane.