General Description
White crystalline solid. Used as an herbicide.
Reactivity Profile
FOMESAFEN is incompatible with acids.
Potential Exposure
Chlorophenoxy herbicide. After July
25, 2003, flumesafen was not permitted in many countries
to be used as an active ingredient on crops except to con trol weeds in soybean crops, and white, kidney and snap
beans. Limited use allowed in some European countries.
Incompatibilities: Slowly hydrolyzes in water, releasing
ammonia and forming acetate salts.
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Seek medical attention immediately.
If this chemical has been inhaled, remove from exposure,
begin rescue breathing (using universal precautions) if
breathing has stopped, and CPR if heart action has stopped.
Transfer promptly to a medical facility. When this chemical
has been swallowed, get medical attention. Do not induce
vomiting when formulations containing petroleum solvents
are ingested. Otherwise, give large quantities of water and
induce vomiting. Do not make an unconscious person
vomit.
Shipping
UN2588 Pesticides, solid, toxic, Hazard Class:
6.1; Labels: 6.1-Poisonous materials, Technical Name
Required.
Description
Fomesafen is a selective herbicide. It is moderately soluble in aqueous solution, is relatively volatile but does have potential to leach to groundwater. It is persistent in soils and aquatic systems. It is moderately toxic to mammals and although a recognised irritant no other significant health issues have been identified. It is not toxic to birds or fish but considered moderately toxic to aquatic crustaceans, honeybees and earthworms.
Chemical Properties
White crystalline solid or powder.
Waste Disposal
Do not discharge into drains
or sewers. Dispose of waste material as a hazardous waste
in a landfill approved and licensed for the disposal of pesti cides. Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Incineration with
effluent gas scrubbing is recommended. 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.
Uses
Fomesafen is a protoporphyrinogen oxidae (PPO) inhibitor.
Definition
ChEBI: Fomesafen is an N-sulfonylcarboxamide that is N-(methylsulfonyl)benzamide in which the phenyl ring is substituted by a nitro group at position 2 and a 2-chloro-4-(trifluoromethyl)phenoxy group at position 5. A protoporphyrinogen oxidase inhibitor, it was specially developed for use (generally as the corresponding sodium salt, fomesafen-sodium) for post-emergence control of broad-leaf weeds in soya. It has a role as a herbicide, an agrochemical and an EC 1.3.3.4 (protoporphyrinogen oxidase) inhibitor. It is an aromatic ether, a N-sulfonylcarboxamide, a C-nitro compound, an organofluorine compound, a member of monochlorobenzenes and a member of phenols. It is a conjugate acid of a fomesafen(1-).
Production Methods
Fomesafen is commercially produced through a multi-step synthesis involving chlorination, esterification, and sulfonamide formation. The synthesis begins with 5-(2-chloro-4-trifluoromethylphenoxy)-2-nitrobenzoic acid, which is first converted into its acid chloride form by refluxing with thionyl chloride. After removing excess thionyl chloride under vacuum, the resulting acid chloride is dissolved in dry pyridine. Methanesulfonamide is then added to this solution, and the mixture is stirred at room temperature overnight to allow for the formation of the sulfonamide linkage. The reaction mixture is subsequently treated with hydrochloric acid and extracted with ether. The organic layer is washed, dried, and evaporated to yield crude fomesafen, which is then purified through crystallisation or chromatography.
Agricultural Uses
Herbicide: After July 25, 2003, flumesafen was not permitted
in many countries to be used as an active ingredient on
crops except to control weeds in soybean crops, and white,
kidney and snap beans. Not approved for use in EU countries. Registered for use in the U.S.
Trade name
BAS 530 04®; FASTER®; FLEX®;
FLEXSTAR; FOMESAFEN® SODIUM; PP 021®;
REFLEX®; REFLEX® 2LC Herbicide (sodium salt);
TORNADO®[C]; TWISTE®[C]; TYPHOON®
Mechanism of action
Selective, absorbed by leaves and roots. Inhibits protoporphyrinogen oxidase (PROTOX), leading to irreversible cell membrane damage.
