Water → 5-Bromo-4-chloro-2-methoxymethoxybenzyl cyanide

To a solution of 5-bromo-4-chloro-2-methoxymethoxybenzyl alcohol (137.9 g) and triethylamine (105 ml) in dichloromethane (500 ml) was added at 0° C. methanesulfonyl chloride (45.5 ml) over a period of 30 minutes. The mixture was stirred overnight (13 hours), while warming up to room temperature. The reaction mixture was poured into water, to which was added dichloromethane for extraction. The extract solution was dried (anhydrous magnesium sulfate) and concentrated. To a suspension of the concentrate and sodium cyanide (51.4 g) in dichloromethane (40 ml) was added dropwise at 0° C. DMSO (300 ml). The mixture was then stirred for 3 hours at room temperature. The reaction mixture was poured into water, which was subjected to extraction with ethyl acetate. The extract solution was washed with water, dried (anhydrous magnesium sulfate) and concentrated. The concentrate was purified by means of a silica gel column chromatography (eluted with ethyl acetate/hexane) to give 5-bromo-4-chloro-2-methoxymethoxybenzyl cyanide (86.4 g) (Compound B-35). The physical properties are shown in [Table 6].