The general procedure for the synthesis of chloromethyltrimethoxysilane from chloromethyltrichlorosilane and trimethyl orthoformate was as follows: 570.2 g (3.1 mol) of chloromethyltrichlorosilane was slowly added dropwise to 1127.8 g (10.64 mol) of trimethyl orthoformate, and the dropwise acceleration was controlled so that the reaction mixture was kept at a slight boiling state. After the dropwise addition was completed, the reaction system was heated to 90°C and the reaction was maintained at this temperature for 5 hours. Upon completion of the reaction, the reaction mixture was purified by distillation, resulting in 449.8 g of the target product chloromethyltrimethoxysilane (Compound 2a). The structure of the product was confirmed by 1H NMR spectrum with the following chemical shifts δ (ppm): 2.77 (single peak, 2H, CH2), 3.58 (single peak, 9H, OCH3).