81777-89-1

Moderately toxic by ingestion, inhalation, and skin contact. A reproductive hazard.

Clomazone is a oxazolidione broadspectrum herbicide used on rice, peas, pumpkins, soybeans, sweet potatoes, winter squash, cotton, tobacco, and fallow wheat fields to control annual grasses and broadleaf weeds.

Move victim to fresh air. Call 911 or emergency medical service. Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Give artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; give artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin. Keep victim warm and quiet. Effects of exposure (inhalation, ingestion, or skin contact) to substance may be delayed.

UN2902 Pesticide, liquid, toxic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required.

Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides.

The molecular target site of clomazone has recently been determined. With clomazone, carotenoid synthesis is inhibited, but no intermediates in the carotenoidcommitted portion of the pathway accumulate (5,6). Synthesis of the derivatives of GGPP (gibberellic acid, phytol, carotenoids) is inhibited by clomazone (5–8). However, the synthesis of certain sesquiterpenoids and triterpenoids is not inhibited (9). Until recently, there was no credible report of the effect of clomazone on any enzyme of the terpenoid pathway (10–12). This was due to the fact that clomazone is a proherbicide and that the proper enzyme had not been tested.

Depending purity, it may be clear and colorless to pale yellow or brownish liquid. Commercially available as emulsifiable concentrates that can be dissolved in water

Do not discharge into drains or sewers. Dispose of waste material as hazardous waste using a licensed disposal contractor to an approved landfill. Consult with environmental regulatory agencies for guidance on acceptable disposal practices. In accordance with 40CFR165, follow recommendations for the disposal of pesticides and pesticide containers. Containers must be disposed of properly by following package label directions or by contacting your local or federal environmental control agency, or by contacting your regional EPA office.

Herbicide.

ChEBI: A oxazolidinone that is 1,2-oxazolidin-3-one substituted by a 2-chlorobenzyl group at position 2 and two methyl groups at position 4.

Herbicide: Clomazone is a broad-spectrum herbicide used on rice, peas, pumpkins, soybeans, sweet potatoes, winter squash, cotton, tobacco and fallow wheat fields to control annual grasses and broadleaf weeds.

CERANO®; COLZOR TRIO®; COMMAND®; COMMENCE®, DIBEL®; FMC® 57020; GAMBIT®; MAGISTER®; MERIT®; STRATEGY®

1. 1000 kg of water was added to a 4000 L reactor followed by 460 kg of 4,4-dimethylisoxazolidin-3-one. The mixture was stirred for 1 hour at room temperature. 2. 383kg of sodium carbonate (Na2CO3) was added to the reaction mixture in small portions. The temperature of the mixture was raised to 85°C and the mixture was stirred continuously at this temperature for 2 hours. 3. 672 kg of o-chlorobenzyl chloride (2-chlorobenzyl chloride) was added slowly and dropwise over a period of 5 hours at 85°C. The mixture was kept at the same temperature for 2 hours. After the dropwise addition was completed, the temperature was maintained at 85°C until the reaction was complete. 4. The reaction mixture was cooled to room temperature, 800 kg of dichloromethane was added and stirred at room temperature for 15 hours. 5. The aqueous phase was separated and the aqueous phase was extracted three times with dichloromethane. 6. Recover the dichloromethane by distillation followed by addition of 2000 kg of hexane to the reactor. The mixture was refluxed for 1 hour, then cooled to 10-15 °C and continued stirring for 1 hour. 7. The solid product was separated by filtration, washed several times with hexane and finally dried under high vacuum to give pure 2-(2-chlorobenzyl)-4,4-dimethyloxazolidin-3-one (815 kg, purity: 96%). Note: Similar results were obtained using sodium hydroxide instead of sodium carbonate as base.

By the preparative incubation of clomazone with microorganisms that have the ability to metabolize clomazone, the metabolites are identified via major biotransformation reactions which involve hydroxylation at the 5-methylene carbon and one of the 3-methyl groups of the isoxazolidone ring and at the 3 0 -position of the phenyl ring. Minor metabolic routes include dihydroxylation on the phenyl ring, cleavage of the isoxazolinone ring, or complete removal of the isoxazolinone ring to form 2-chlorobenzyl alcohol. Under aerobic conditions of soils, degradation of clomazone proceeds primarily by CO2 evolution and the formation of bound soil residues. In flooded soils, clomazone is found rapidly to degrade via the formation of the reductive product N-[(2-chlorophenyl)methyl]-3-hydroxy-2,2- dimethylpropionamide. In tolerant soybean cell suspension cultures, the only metabolite identified is b-glycosyl-2-chlorobenzyl alcohol.

Store at -20°C

[1] Patent: WO2015/353, 2015, A1. Location in patent: Page/Page column 16; 17
[2] Patent: CN106749072, 2017, A. Location in patent: Paragraph 0018; 0021; 0024; 0027