Abstract Upon the chlorination of vinyl compounds in alcohols, the reaction products were composed of 2-alkoxy-1-chloro compound (A), 1-alkoxy-2-chloro compound (B) and vicinal dichloride (C). Various vinyl compounds were chlorinated in alcohols at 40 °C in order to elucidate the effect of their molecular structure on the product distribution. The A/(A+B) was inversely proportional to the relative rate of ordinary chlorination in carbon tetrachloride. The A/(A+B) for the chlorination of allyl chloride in methanol was little affected by the reaction conditions: (1) reaction temperature, (2) mole ratio, and (3) elapse of time. However, the A/(A+B) increased with increasing Es value of the alkyl group of alcohol.