Sethoxydim 烯禾啶

烯禾啶

CAS No. : [74051-80-2]
英文名称: Sethoxydim
化学名称：（±）2－［1－（乙氧亚氨基）丁基］－5－（2－乙硫基丙基）－3－羟基环己－2－烯酮 ；2-[1-(ethoximino)butyl]-5-[2-(ethylthio)-propyl]-3-hydroxy-2-cyclohexen-1-one;
其他名称：拿捕净，稀禾定，乙草丁，硫乙草丁
分子式：C17H29NO3S
分子量：327.5

理化性质：本品为淡黄色渍状液体，无臭味。沸点b.p.>90℃/4×10-3Pa，相对密度1.05(20℃)，蒸气压：<0.013 mpa(25℃，)能溶于甲醇、辛醇、醋酸乙酯、己烷、苯、二甲苯等多种有机溶剂，在水中溶解25mg/L (pH=4)，4.7g/L (pH=7)。土壤中半衰期<1d (15℃)，

毒性：大鼠急性经口LD503200～3500mg/kg，急性经皮LD50>5000mg/kg，急性吸入LC50>6.28mg/L (4h)。对兔皮肤和眼睛无刺激作用。大鼠3年饲喂试验无作用剂量360mg/kg。在试验条件下，未见致畸、致癌、致突变作用。鲤鱼LC50148mg/L （96h)，鹌鹑急性经口LD50>5000mg/kg；对蜜蜂无明显危害。

作用特点及杀草谱：环己烯酮类除草剂，选择性很强的内吸传导型茎叶处理剂，能被禾本科杂草茎叶迅速吸收，并传导到顶端和节间分生组织，使细胞分裂破坏致死。可用于大豆、棉花、油菜、花生、马铃薯、甜菜、向日葵、亚麻等作物及果园，防除稗草、野燕麦、狗尾草、看麦娘、马唐、牛筋草等，对阔叶杂草无效。如防治大豆、棉花地杂草，分别用20%乳油10～20mL/100m2对水喷雾，或用12.5%机油乳油10～15mL/100m2对水喷雾。

剂型：20%乳油、12.5%机油，

生产方法 ：
1、 ETO的制备 以丁烯-2-醛为原料，在伯胺催化下，与乙硫醇加成，生成3-乙硫基丁醛；乙酰乙酸甲酯水氏妥生成乙酰乙酸钠；然后将3-乙硫基丁醛与乙酰乙酸钠作用，以N-甲基己胺为催化剂，在20～40℃反应生成6-乙硫基-3-庚烯-2-酮（简称ETO）。
2、CDNA的制备 ETO在甲醇钠存在下与丙二酸二甲酯发生迈克尔（Michel)加成，然后经环合、水解、脱羧反应，得5-[2-（乙硫基）丙基]-1，3-环己二酮（简称CDNA）。
3、稀禾定的合成 CDNA以丁酰氯为酰化剂进行酰化反应，由于丁酰氯易于水解，反应应在有机溶剂中进行，需采用相转移催化剂，酰化产物在4-N，N-二甲基吡啶催化作用下发生转位重排。重排产物再与乙氧基胺在40～60℃温和条件下进行缩合成肟，以较高收率制得稀禾定。
生产情况：沈阳化工研究院试验厂；沧州科润化工有限公司；山东先达化工有限公司；浙江瑞丰控股有限公司；昆山瑞泽农药有限公司；江苏徐州神农化工有限公司

sethoxydim
Herbicide
HRAC A WSSA 1; cyclohexanedione oxime

NOMENCLATURE
Common name sethoxydim (BSI, draft E-ISO); séthoxydime ((f) draft F-ISO)
IUPAC name (?-(EZ)-2-(1-ethoxyiminobutyl)-5-[2-(ethylthio)propyl]-3-hydroxycyclohex-2-enone
Chemical Abstracts name (?-2-[1-(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one (i); first publication on the compound presented the structure as a tautomer, 2-[1-(ethoxyamino)butylidene]-5-[2-(ethylthio)propyl]-1,3-cyclohexanedione (ii)
CAS RN [74051-80-2] (i); [71441-80-0] (ii) EEC no. 277-682-3 (for i) Development codes NP-55 (Nippon Soda); BAS 90 520H (BASF); SN 81 742 (AgrEvo)

PHYSICAL CHEMISTRY
Mol. wt. 327.5 M.f. C17H29NO3S Form Oily, odourless liquid. B.p. >90 ºC/3 ´ 10-5 mmHg V.p. <0.013 mPa KOW logP = 4.51 (pH 5), 1.65 (pH 7) S.g./density 1.043 at 25 ºC Solubility In water 25 (pH 4), 4700 (pH 7) (both in mg/l, 20 ºC). Soluble in most common organic solvents e.g. acetone, benzene, ethyl acetate, hexane, methanol all >1 kg/kg (25 ºC). Stability The commercial product is stable for at least 2 y under normal storage conditions. At 10 mg/l, 12 h/d illumination with xenon lamp, DT50 is 5.5 d (pH 8.7, 25 ºC).

COMMERCIALISATION
History Introduced in USA (1983) by Nippon Soda Co., Ltd. Patents JP 52112945; US 4249937; UK 1589003; DE 2822304. Manufacturers Nisso BASF Agro; Shenyang

APPLICATIONS
Biochemistry Fatty acid synthesis inhibitor, by inhibition of acetyl CoA carboxylase (ACCase). Inhibits mitosis. Mode of action Selective systemic herbicide, absorbed predominantly by the foliage, and, to a lesser extent, by the roots. Translocated rapidly both acropetally and basipetally. Uses Control of annual (at 0.20-0.25 kg/ha) and perennial (0.2-0.5 kg/ha) grasses (except Poa spp.) in broad-leaved crops, including cotton, oilseed rape, soya beans, sugar beet, fodder beet, sunflowers, spinach, potatoes, tobacco, peanuts, strawberries, alfalfa, flax, and vegetables. Phytotoxicity Non-phytotoxic to broad-leaved crops, but phytotoxic to most monocotyledonous crops (except onions, garlic, and asparagus). Formulation types EC. Compatibility Incompatible with organic and inorganic copper compounds. Selected products: 'Nabu' (Nippon Soda); 'Poast' (BASF)

OTHER PRODUCTS
'Checkmate' (Certis UK); 'Conclude G' (BASF); 'Fervinal' (Certis); 'Grasidim' (Sipcam); 'Manifest G' (BASF); 'Prestige' (BASF); 'Torpedo' (BASF); 'Ultima 160' (BASF); 'Vantage' (BASF) mixtures: 'Conclude Ultra' (+ acifluorfen-sodium+ bentazone-sodium) (BASF); 'Rezult' (+ bentazone-sodium) (BASF)

ANALYSIS
Product analysis by hplc with u.v. detection (CIPAC Handbook, 1992, E, 193-6). Residues determined by hplc.

MAMMALIAN TOXICOLOGY
Oral Acute oral LD50 for male rats 3200, female rats 2676, male mice 5600, female mice 6300 mg/kg. Skin and eye Acute percutaneous LD50 for rats and mice >5000 mg/kg. Non-irritating to skin and eyes (rabbits); no skin sensitisation. Inhalation LC50 (4 h) for rats >6.28 mg/l air. NOEL (2 y) for rats 17.2, mice 13.7 mg/kg b.w. daily. ADI (Japan) 0.14 mg/kg. Toxicity class WHO (a.i.) III; EPA (formulation) III

ECOTOXICOLOGY
Birds Acute oral LD50 for Japanese quail >5000 mg/kg. Fish LC50 (48 h) for carp 153, trout 38 mg tech./l. Daphnia LC50 (3 h) 1.5 mg/l. Bees No significant hazard to bees.

ENVIRONMENTAL FATE
Animals In rats, following oral administration, 78.5% is eliminated in the urine and 20.1% in the faeces within 48 h. Plants In soya beans, the parent molecule is oxidised, structurally rearranged, and conjugated. Transformation to metabolites is very rapid. Soil/Environment DT50 in soil <1 d at 15 ºC. Metabolism involves molecular rearrangement, oxidation and conjugation processes.