Fenoprop

{{chembox

| ImageFile = fenoprop.png

| ImageSize =

| PIN = rac-(2R)-2-(2,4,5-trichlorophenoxy)propanoic acid

| OtherNames = 2-(2,4,5-Trichlorophenoxy)propionic acid
Silvex

|Section1={{Chembox Identifiers

| Abbreviations = 2,4,5-TP

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID = 6891

| KEGG_Ref = {{keggcite|correct|kegg}}

| KEGG = C14532

| InChI = 1/C9H7Cl3O3/c1-4(9(13)14)15-8-3-6(11)5(10)2-7(8)12/h2-4H,1H3,(H,13,14)

| InChIKey = ZLSWBLPERHFHIS-UHFFFAOYAC

| ChEMBL_Ref = {{ebicite|correct|EBI}}

| ChEMBL = 460296

| ChEBI = 34758

| UNII = D2HZL58IS3

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| StdInChI = 1S/C9H7Cl3O3/c1-4(9(13)14)15-8-3-6(11)5(10)2-7(8)12/h2-4H,1H3,(H,13,14)

| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

| StdInChIKey = ZLSWBLPERHFHIS-UHFFFAOYSA-N

| CASNo = 93-72-1

| CASNo_Ref = {{cascite|correct|CAS}}

| PubChem = 7158

| SMILES = Clc1cc(OC(C(=O)O)C)c(Cl)cc1Cl

}}

|Section2={{Chembox Properties

| Properties_ref = {{cite web |url=http://sitem.herts.ac.uk/aeru/ppdb/en/Reports/300.htm |title=Fenoprop |publisher=University of Hertfordshire |author=Pesticide Properties Database |access-date=2021-03-11}}

| Formula = C₉H₇Cl₃O₃

| MolarMass = 269.51

| Appearance = White powder

| Density = 1.21 g/cm³ at 20 °C

| MeltingPtC = 180

| BoilingPt =

| Solubility =

| LogP = 3.8 (20 °C)

| pKa = 2.84

}}

|Section3={{Chembox Hazards

| MainHazards =

| FlashPt =

| AutoignitionPt =

}}

}}

Fenoprop, also called 2,4,5-TP, is the organic compound 2-(2,4,5-trichlorophenoxy)propionic acid.{{cite web |url=http://www.alanwood.net/pesticides/ |title=Compendium of Pesticide Common Names|website=alanwood.net}} It is a phenoxy herbicide and a plant growth regulator, an analog of 2,4,5-T in which the latter's acetic acid sidechain is replaced with a propionate group (with an extra CH₃). The addition of this extra methyl group creates a chiral centre in the molecule and useful biological activity is found only in the (2R)-isomer.{{cite book |isbn=9780080951683 |title=Comprehensive Chirality |date=31 December 2012 |url=https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/dichlorprop |last1=Wendeborn|first1=S.|last2=Smits|first2=H. |chapter=Synthetic Auxins |editor1=Erick M. Carreira |editor2=Hisashi Yamamoto }} The compound's mechanism of action is to mimic the auxin growth hormone indoleacetic acid (IAA).{{Cite journal|last=Grossmann|first=K.|year=2010|title=Auxin herbicides: current status of mechanism and mode of action.|journal=Pest Management Science|volume=66|issue=2|pages=2033–2043|doi=10.1002/ps.1860|pmid=19823992}} When sprayed on plants it induces rapid, uncontrolled growth. As with 2,4,5-T, fenoprop is toxic to shrubs and trees.

The name Silvex was used in the USA but it has been banned from use there since 1985. According to the Environmental Protection Agency its greatest use was as a postemergence herbicide for control of woody plants, and broadleaf herbaceous weeds in rice and bluegrass turf, in sugarcane, in rangeland improvement programs and on lawns.{{cite web |url=https://archive.epa.gov/water/archive/web/pdf/archived-consumer-factsheet-on-2-4-5-tp.pdf |title=Consumer Factsheet on: 2,4,5-TP (SILVEX)|author=US Environmental Protection Agency|access-date=2021-03-11}}

Fenoprop and some of its esters were in use from 1945 but are now obsolete.