Propachlor

Propachlor (2-chloro-N-isopropylacetanilide) is an anilide used primarily as an herbicide first marketed by Monsanto under the tradename Ramrod. It was initially registered for use in the United States in 1964. The preparation acts on annual grasses and on some broadleaf weeds and was briefly sold in the UK as a germination inhibitor under the name Murphy Covershield. Propachlor was sold in flake, pelletized, and concentrated liquid formulations, which contained Propachlor as the main ingredient, or as a mixture with Atrazine or Propazine. Propazine-only formulations typically included instructions for mixing with Atrazine. Between 1987 and 1996, about 2.1 million pounds of its active ingredient were used in the United States. 75% was applied to sorghum crops and 24% to maize. Monsanto voluntarily discontinued its manufacture in 1998. It is currently listed in the U.S. Environmental Protection Agency's Toxics Release Inventory. In 2008, the European Commission issued a decision withdrawing its approval for use as of March 18, 2009, citing the presence of its metabolites in groundwater. Propachlor was added to California's Proposition 65 list as a carcinogen in 2001.

Propachlor

Names
Preferred IUPAC name 2-Chloro-N-phenyl-N-(propan-2-yl)acetamide
Other names 2-Chloro-N-isopropylacetanilide N-Isopropyl-2-chloroacetanilide Ramrod (trade name) Bexton (trade name) Nitacid (trade name) Satecid (trade name)
Identifiers
CAS Number	1918-16-7
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL1394829
ChemSpider	4762
ECHA InfoCard	100.016.036
PubChem CID	4931
UNII	015443A483 Y
CompTox Dashboard (EPA)	DTXSID4024274
InChI InChI=1S/C11H14ClNO/c1-9(2)13(11(14)8-12)10-6-4-3-5-7-10/h3-7,9H,8H2,1-2H3 Key: MFOUDYKPLGXPGO-UHFFFAOYSA-N InChI=1/C11H14ClNO/c1-9(2)13(11(14)8-12)10-6-4-3-5-7-10/h3-7,9H,8H2,1-2H3 Key: MFOUDYKPLGXPGO-UHFFFAOYAZ
SMILES CC(C)N(c1ccccc1)C(=O)CCl
Properties
Chemical formula	C11H14ClNO
Molar mass	211.69 g·mol−1
Appearance	light tan solid
Density	1.139 g/mL
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Chemical compound

Propachlor (2-chloro-N-isopropylacetanilide)^[1] is an anilide used primarily as an herbicide first marketed by Monsanto under the tradename Ramrod. It was initially registered for use in the United States in 1964.^[2][3]

The preparation acts on annual grasses and on some broadleaf weeds ^[1] and was briefly sold in the UK as a germination inhibitor under the name Murphy Covershield. Propachlor was sold in flake, pelletized, and concentrated liquid formulations, which contained Propachlor as the main ingredient, or as a mixture with Atrazine or Propazine. Propazine-only formulations typically included instructions for mixing with Atrazine.^[3]

Between 1987 and 1996, about 2.1 million pounds of its active ingredient were used in the United States.^[4] 75% was applied to sorghum crops and 24% to maize.^[4]

Monsanto voluntarily discontinued its manufacture in 1998.^[5] It is currently listed in the U.S. Environmental Protection Agency's Toxics Release Inventory.^[6] In 2008, the European Commission issued a decision withdrawing its approval for use as of March 18, 2009, citing the presence of its metabolites in groundwater.^[7] Propachlor was added to California's Proposition 65 list as a carcinogen in 2001.^[8]

Current manufacturers

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It is currently being produced by Makhteshim Agan Group and Shenzhen Qinfeng Pesticides Co., Ltd.^[9]

References

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1. ^ ^{a b} Warholic, DT; Gutenmann, WH; Lisk, DJ (1983). "Propachlor herbicide residue studies in cabbage using modified analytical procedure". Bulletin of Environmental Contamination and Toxicology. 31 (5): 585–7. Bibcode:1983BuECT..31..585W. doi:10.1007/bf01605479. PMID 6640157.
2. ^ "Propachlor (Ramrod, Bexton) Herbicide Profile 2/85". Cornell University. Retrieved 2009-09-09.
3. ^ ^{a b} "Propachlor - Reregistration Eligibility Decision (R.E.D.) Facts" (PDF). US Environmental Protection Agency. November 1998. Retrieved 12 January 2025.
4. ^ ^{a b} "Reregistration Eligibility Decision (RED) - Propachlor" (PDF). U.S. Environmental Protection Agency. Archived from the original (PDF) on October 2, 2000. Retrieved 2009-09-09.
5. ^ "Illinois Pesticide Review". University of Illinois Extension Service. Retrieved 2009-09-09.
6. ^ "Toxics Release Inventory (TRI) Chemicals in TOXMAP". Archived from the original on September 17, 2005. Retrieved 2009-09-09.
7. ^ "COMMISSION DECISION of 18 September 2008 concerning the non-inclusion of propachlor in Annex I to Council Directive 91/414/EEC and the withdrawal of authorisations for plant protection products containing that substance". European Commission. Retrieved 2009-09-09.
8. ^ "CHEMICALS KNOWN TO THE STATE TO CAUSE CANCER OR REPRODUCTIVE TOXICITY AUGUST 7, 2009" (PDF). State of California Environmental Protection Agency. Retrieved 2009-09-09.
9. ^ Farm Chemicals International (2012-03-12). "Propachlor". Retrieved 2012-06-27.

External links

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• Propachlor in the Pesticide Properties DataBase (PPDB)