Sethoxydim

Sethoxydim

CAS No.: [74051-80-2] 

English name: Sethoxydim 

Chemical name: (±) 2 - [1 - (ethoxy imino) butyl] -5-- (2 - ethylthio propyl) -3-- hydroxy cyclohexyl -2-- enone; 2 - [1 - ( ethoximino) butyl] -5 - [2 - (ethylthio)-propyl]-3-hydroxy-2-cyclohexen-1-one; 

Other names: Arrest net, thin set Wo, B Grass D, S B D grass 

Molecular formula: C17H29NO3S 

Molecular weight: 327.5 

Structure: 

Properties: Light yellow liquid stains, no odor. Boiling point bp> 90 ℃ / 4 × 10-3Pa, the relative density of 1.05 (20 ℃), vapor pressure: <0.013 mpa (25 ℃,) can be dissolved in methanol, octanol, ethyl acetate, hexane, benzene, xylene and other organic solvents, dissolved in water 25mg / L (pH = 4), 4.7g / L (pH = 7). Soil half-life <1d (15 ℃), 

Toxicity: Acute oral LD503200 ~ 3500mg/kg, acute dermal LD50> 5000mg/kg, acute inhalation LC50> 6.28mg / L (4h). Rabbit skin and eyes-free stimulation. 3-year feeding experiment in rats had no effect dose of 360mg/kg. Under the experimental conditions, no teratogenic, carcinogenic, mutagenic effect. Carp LC50148mg / L (96h), quail acute oral LD50> 5000mg/kg; no significant harm to bees. 

Characteristics and role spectrum herbicide: cyclohexene herbicides, selective absorption conduction within a strong stem and leaf treatment agent, leaf weeds can be quickly absorbed, and transmitted to the top of the meristem and internode , so that destruction of cell division to death. Can be used for soybean, cotton, rapeseed, peanut, potato, sugar beet, sunflower, flax and other crops and orchards, Control of barnyard grass, wild oats, Setaria viridis, Alopecurus, crabgrass, goosegrass, etc., on the broad-leaved weeds invalid. Such as the prevention and control of soybean, cotton grass, with 20%, respectively, EC 10 ~ 20mL/100m2 water spray, or 12.5% of EC 10 ~ 15mL/100m2 oil on the water spray. 

Formulation: 20% EC, 12.5% oil, 

Production methods: 

1, ETO preparation in order to butene -2-- aldehyde, amine in the catalyst, and ethanethiol addition, 3 - B S butyraldehyde; Methyl properly build water's sodium acetoacetate; then the 3 - B S butyraldehyde and sodium acetoacetate role in N-methyl-cyclohexylamine as a catalyst in the reaction of 20 ~ 40 ℃ 6 - ethylthio -3-- heptene -2-- one (referred to as ETO). 

2, CDNA preparation of ETO in the presence of sodium methoxide and methyl malonate occurs Michael (Michel) addition, and then by cyclization, hydrolysis, decarboxylation, was 5 - [2 - (ethylthio) propyl] -1,3 - cyclohexanedione (referred to as CDNA). 

3, the synthesis of thin CDNA Wo be to the small chloride as acylating acylation agents, due to easy hydrolysis of butyryl chloride, the reaction should be carried out in an organic solvent, requires the use of phase transfer catalyst, acylation products in 4-N, N- dimethyl pyridine catalyst translocation rearrangement occurs. Rearrangement product again and ethoxylated amines in 40 ~ 60 ℃ under mild conditions Synthesis of oxime reduction to the higher yield obtained Wo be thin.