Abstract: 1,2,3-Trichloropropene and 1,1,2,3-tetrachloropropene have been pre-parad in 86% yield by the following procedure:1.Dehydrochlorination of 1,2,3-Trichloropropane with 30% Sodium hydroxide and a surfactant gives 90-92% yields of 2,3-dichloropropen(I).2.Catalytic chlorination of 2,3-dichloropropene (I) with AlCl3 at 85℃ gives a mixture of 37% 1,2,2,3-tetrechloropropane (Ⅱ) and 53% 1,1,2,2,3-pentachloropropane (Ⅲ).3.Dehydrochlorination of (Ⅱ) and (Ⅲ) with 30% Sodium hydroxide and a surfactant to give a mixture of 39% 1,2,3-Trichloropropene (Ⅳ) and 43% 1,1,2,3-Tetrachloropropene (V).The total yield is 86%.Reaction mixture of (Ⅳ) and (V) with diisopropylamine and carbon-oxysulfide gives a herbicidal mixture of 33-39% S-(2,3-dichloroallyl) diisopropylthiolcarbamate (Diallate) (Ⅵ) and 47-53% S-(2,3,3-Trichloroallyl) diisopropylthiolcarbamate (Triallate) (Ⅶ), The total yield is above 80%.