Triflusulfuron-methyl

Description

Triflusulfuron-methyl is a s ulfonylurea herbicide. It is moderately soluble in water and has a low volatility. It is not expected to be persistent in soil systems but may be persistent in water depending on local conditions. It is not expected to leach to groundwater. Whilst its toxicity to aquatic plants is high, toxicity to most other species is moderate to low. Triflusulfuron-methyl has a low oral mammalian toxicity and is thought to be a respiratory tract irritant. It is possible that this substance is carcinogenic.

Chemical Properties

The m.p. of this product is 160~163°C, dissociation constant pKa4.4. Solubility in water at 25°C: 1mg/L (pH=3), 3mg/L (pH=5), 110mg/L (pH=7), 11000mg/L (pH=9). Partition coefficient 9.2. Half-life in water at 25°C is 3.7d (pH=5), 32d (pH=7), 36d (pH=9). Rapidly degraded in soil, under alkaline conditions, mainly by microbial degradation; under neutral and acidic conditions, mainly by chemical hydrolysis. The half-life in soil under laboratory conditions is 3-6d.

Uses

Herbicide.

Definition

ChEBI: Triflusulfuron-methyl is a methyl ester resulting from the formal condensation of the carboxy group of triflusulfuron with methanol. A proherbicide for triflusulfuron. It has a role as a proherbicide, an agrochemical and an EC 2.2.1.6 (acetolactate synthase) inhibitor. It is a benzoate ester, a methyl ester, a N-sulfonylurea, a member of 1,3,5-triazines, a tertiary amino compound, an aromatic ether and an organofluorine compound. It is functionally related to a triflusulfuron.

Production Methods

In industrial settings, the synthesis of triflusulfuron-methyl begins with the preparation of a triazine ring system, typically derived from cyanuric chloride, which undergoes sequential substitution with fluorinated aromatic amines and methoxy groups. This intermediate is then reacted with a sulfonyl isocyanate or sulfonamide to form the characteristic sulfonylurea bridge, a key functional group responsible for herbicidal activity. The process requires precise control of temperature, solvent conditions, and pH to ensure high purity and yield.

Mechanism of action

Inhibits acetolactate synthase (ALS), an enzyme essential for amino acid synthesis in plants

Pesticide Type

Herbicide