Dichloroethane in the organic solvent, 6-hydroxy -Chloro - octanoic acid ethyl ester with chlorinated reagent solid phosgene inN, N-dimethyl benzyl amine for the acid-binding agentEthyl 6-hydroxy-8-chlorooctanoate,Chlorination reagents,N, N-dimethylbenzylamine molar ratio1: 1.05: 0.12,The organic solvent was reacted with 6-hydroxy-8-The weight ratio of ethyl chlorocaprylate was1: 2.4 at a temperature ofN, N-dimethylbenzylamine was added dropwise at 10℃,Insulation temperature of 75 ,Insulation time 150min,In the reaction solution obtained,Water layer, water and 6 - hydroxy -8-chloro-ethyl octanoate weight ratio of 1:3, the upper organic phase.Vacuum distillation to collect vacuum 5mmHg,A temperature of 172-176℃,Ethyl 6,8-dichlorooctanoate,Product mol yield 95.68%, Purity 96.65%The bottom of the liquid base to adjust the pH value of 11,Layered,The upper layer was dewatered with sodium sulfateN, N-dimethylbenzylamine,The molar yield of the product was 96.69%Purity 99.71%.