Clethodim

Structural formula
	Simplified structural formula of a complex mixture of stereoisomers
General
Surname	Clethodim
other names	(5 RS ) -2 - {(1 EZ ) -1 - [(2 E ) -3-chloroallyloxyimino] propyl} -5 - [(2 RS ) -2- (ethylthio) propyl] -3-hydroxycyclohex-2- en-1-on ( IUPAC )
Molecular formula	C 17 H 26 ClNO 3 S
Brief description	yellow liquid
External identifiers / databases
EC number	619-396-7
ECHA InfoCard	100.128.422
PubChem	6444391
Wikidata	Q2642646
properties
Molar mass	359.91 g mol −1
Physical state	liquid
density	1.1395 g cm −3
Melting point	−80 ° C
boiling point	133 ° C (decomposition)
pK s value	4.47
solubility	soluble in water (0.54 g / 100 ml at pH 7) and most organic solvents
safety instructions
GHS hazard labeling from Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary Caution
H and P phrases	H: 302-317-412
	EUH: 066
	P: 273
Toxicological data	1133 mg kg −1 ( LD 50 , rat , oral ) ; > 4167 mg kg −1 ( LD 50 , rat , transdermal ) ;
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Clethodim is a mixture of several isomeric chemical compounds from the group of cyclohexene - oximes . The name Clethodim was originally approved for the substance with the ( E ) configuration at the C = N double bond , but in 2008 the manufacturer determined that the ( Z ) isomer was also present in the manufactured product and requested that the Definition will be changed.

Extraction and presentation

Clethodim can be obtained by reacting ethyl mercaptan with crotonaldehyde , followed by treatment with acetone , dimethyl malonate , hydrolysis reagents, propionic acid chloride and chlorohydroxyallylamine .

Another production process involves the reaction of 5-propyl-2-thioethyl-cyclohexane-1,3-dione with propionyl chloride , aluminum (III) chloride and 1-chloro-3-allyloxyamine .

properties

Clethodim is a yellow oily liquid that is soluble in water and most organic solvents . The carbon atom at position 5 also appears to have chirality , but is not considered to be a chiral center because of the rapid keto-enol tautomerism .

use

Clethodim is used as a herbicide . It is a post-emergence herbicide, active against annual and perennial grasses and similar weeds with narrow leaves. It belongs to the class of acetyl-CoA carboxylase inhibitors, which contains the compounds sethoxydim and cycloxydim, and was approved in around 35 countries in over 20 crops in 1994.

Admission

The application for approval of the active substance in the EU was withdrawn after the applicant received a draft assessment report in April 2006. As a result, Clethodim was not included in the list of permissible active substances in Decision 2008/934 / EC. Subsequent applications were made for inclusion in the list of permitted active ingredients and approved in 2011 with the stipulation that only uses as pesticides for sugar beet may be permitted. The restriction on sugar beet was lifted in February 2012.

In a number of EU countries, including Germany and Austria, as well as Switzerland, plant protection products (e.g. Select) containing this active ingredient are approved.

Individual evidence

↑ ^a ^b ^c ^d ^e ^f FAO: clethodim (PDF; 268 kB), accessed on February 7, 2018.

↑ ^a ^b ^c ^d ^e EFSA: Conclusion on the peer review of the pesticide risk assessment of the active substance clethodim. In: EFSA Journal. 9, 2011, p. 2417, doi : 10.2903 / j.efsa.2011.2417 .

^ Entry on Clethodim in the GESTIS substance database of the IFA , accessed on December 29, 2019(JavaScript required) .

↑ Entry on clethodim (ISO); (5RS) -2 - {(1EZ) -1 - [(2E) -3-chloroallyloxyimino] propyl} -5 - [(2RS) -2- (ethylthio) propyl] -3-hydroxycyclohex-2-en-1- one in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on December 29, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .

↑ Clethodim data sheet at Sigma-Aldrich , accessed on December 29, 2019 ( PDF ).

↑ ^a ^b alan wood: clethodim , accessed on 7 February 2018th

^ Entry on Clethodim in the Hazardous Substances Data Bank , accessed June 17, 2013.

↑ Thomas A. Unger: Pesticide synthesis handbook . 1996, ISBN 978-0-8155-1401-5 , pp. 148 (English, limited preview in Google Book search).

↑ Directive 2011/21 / EU of the Commission of March 2, 2011 amending Council Directive 91/414 / EEC to include the active ingredient Clethodim and amending Decision 2008/934 / EC

↑ Implementing Regulation (EU) No. 87/2012 of the Commission of February 1, 2012 amending Implementing Regulation (EU) No. 540/2011 with regard to the conditions for the approval of the active ingredient Clethodim

↑ General Directorate Health and Food Safety of the European Commission: Entry on Clethodim in the EU pesticide database; Entry in the national registers of plant protection products in Switzerland , Austria and Germany ; Retrieved February 20, 2016.

[FAO-1] ↑ ^a ^b ^c ^d ^e ^f FAO: clethodim (PDF; 268 kB), accessed on February 7, 2018.

[EFSA-2] EFSA: Conclusion on the peer review of the pesticide risk assessment of the active substance clethodim. In: EFSA Journal. 9, 2011, p. 2417, doi : 10.2903 / j.efsa.2011.2417 .

[GESTIS-3] Entry on Clethodim in the GESTIS substance database of the IFA , accessed on December 29, 2019(JavaScript required) .

[CLP_100.128.422-4] Entry on clethodim (ISO); (5RS) -2 - {(1EZ) -1 - [(2E) -3-chloroallyloxyimino] propyl} -5 - [(2RS) -2- (ethylthio) propyl] -3-hydroxycyclohex-2-en-1- one in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on December 29, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .