POTASSIUM TELLURATE

Uses

Pyraflufen-ethyl is a derivative of Pyraflufen (P840450), an herbicide used in the protection of crops.

Production Methods

Pyraflufen-ethyl is commercially produced via a multi-step synthesis starting from 2-chloro-5-(trifluoromethyl)aniline, which undergoes diazotization with sodium nitrite/HCl followed by Sandmeyer reaction with CuCN to yield 2-chloro-5-(trifluoromethyl)benzonitrile. This nitrile is nitrated at the 4-position using nitric-sulphuric acid, then reduced via catalytic hydrogenation (Pd/C) or Fe/HCl to form 5-amino-2-chloro-4-fluorobenzonitrile. Condensation with ethyl 2-chloroacetoacetate in the presence of sodium ethoxide in ethanol constructs the pyrrole ring through nucleophilic substitution and cyclisation. Final N-alkylation with ethyl bromodifluoroacetate using potassium carbonate in DMF produces pyraflufen-ethyl.

Definition

ChEBI: Pyraflufen-ethyl is an ethyl ester resulting from the formal condensation of the carboxy group of pyraflufen with ethanol. A proherbicide for pyraflufen, it is used for the control of broad-leaved weeds and grasses in a variety of crops. It has a role as an EC 1.3.3.4 (protoporphyrinogen oxidase) inhibitor, a proherbicide and an agrochemical. It is a member of pyrazoles, a biaryl, an ethyl ester, an aromatic ether, a member of monochlorobenzenes and a member of monofluorobenzenes. It is functionally related to a pyraflufen.

Mechanism of action

Selective with contact action. Inhibition of protoporphyrinogen oxidase (PPO) - cell membrane disruption

Pesticide Type

Herbicide