Dimethyl tetrachloroterephthalate (DCPA, Dacthal) is an organic compound with the formula C6Cl4(CO2CH3)2. It is a colourless solid, although commercial samples can be off white. DCPA is the dimethyl ester of tetrachloroterephthalic acid. It is used as a preemergent herbicide. It kills grass and many common weeds without killing sensitive plants such as flowers, fruits, vegetables, turf, and cotton. DCPA was first registered for use in the United States in 1958. Production of DCPA was eventually discontinued by ISK Biosciences in 1998, but the large manufacturing company AMVAC began producing the product in 2001 for use in America. Sigma-Aldrich also manufactures DCPA for use in the USA under the name Pestanal. In Australia, DCPA is the active ingredient in agchem company Farmalinx's herbicide called Dynamo 750. Currently, DCPA is only used for eggplant, kale, turnips, and sweet potatoes.

CAS：1861-32-1
中文别名：TCTP;2,3,5,6-四氯-1,4-苯二甲酸甲酯;氯酞酸二甲酯;2,3,5,6-四氯对苯二甲酸二甲酯;四氯对苯二甲酸二甲酯;二甲基敌草索;敌草索;
英文别名：DIMETHYL 2,3,5,6-TETRACHLOROTEREPHTHALATE;dimethyl tetrachloroterephthalate;Tetrachloroterephthalic Acid Dimethyl Ester;Tetral;Dacthalor;dimethyl 2,3,5,6-tetrachlorobenzene-1,4-dicarboxylate;Chlorthal-dimethyl,Dimethyl tetrachloroterephthalate;Tetrachloroterephthalic acid dimethyl ester;Chlorthal-methyl;Fatal;DCPA;1,4-dimethyl 2,3,5,6-tetrachloro-1,4-benzenedicarboxylate;chlorthal;Dimethyl Tetrachloroterephthalate;dacthal;Dimethyl tetrachloroterephthalate;dimethyl 2,3,5,6-tetra-chloroterephthalate;DIMETHYL TETRACHLOROTEREPHTHALATE;Chlorthal-dimethyl;
分子式：C10H6Cl4O4
分子量：331.964
精确质量：329.902
Psa：52.6
Logp：3.8734

EINECS号：217-464-7
MDL号：MFCD00014902
BRN号：1888840
RTECS号：WZ1500000

外观与性状：无色,结晶固体
密度：1.558g/cm3
沸点：422ºC at 760mmHg
熔点：155-156°C
闪点：174.7ºC
折射率：1.564
水溶解性：0.05 g/100 mL
稳定性：Stable in the pure state stable to UV irradiation.
储存条件：Keep closed in a cool, dry place. Store only with compatible chemicals.
蒸汽压：2.5E-07mmHg at 25°C

RTECS号：WZ1500000
安全说明：S22-S24/25
海关编码：2917399090

生产方法
采用强甲基化剂(如重氮甲烷或硫酸二甲酯),使四氯对苯二甲酸烷基化;或由四氯对苯二甲酰氯与甲醇酯化而得。中间体四氯对苯二甲酰氯有两种主要合成方法。 除草剂。对萌发至二叶期的稗草有显著的活性,对旱地马唐等芽前杂草也有良好的防除效果。
用途
除草剂。对萌发至二叶期的稗草有显著的活性,对旱地马唐等芽前杂草也有良好的防除效果。