MCPA

Description

2-Methyl-4-chlorophenoxyacetic acid · CAS 94-74-6 · C9H9ClO3. UNII D888C394VO. Melting Point: 118-119 °C; Melting Point: 113-119 °C; Density: 1.56 @ 25 °C/15.5 °C.

Identification

CAS Registry Number	94-74-6
PubChem CID	7204
Molecular formula	C9H9ClO3
IUPAC name	2-(4-chloro-2-methylphenoxy)acetic acid
UNII (FDA)	D888C394VO

Computed Descriptors

Molecular Weight	200.62
XLogP3	2.6
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	3
Rotatable Bond Count	3
Exact Mass	200.0240218
Monoisotopic Mass	200.0240218
Topological Polar Surface Area	46.5
Heavy Atom Count	13
Formal Charge	0

Physical & Chemical Properties

Melting Point	118-119 °C
Melting Point	113-119 °C
Density	1.56 @ 25 °C/15.5 °C
Vapor Pressure	0.0000059 [mmHg]
Vapor Pressure	5.90X10-6 mm Hg
LogP	log Kow = 3.25
LogP	2.8
LogP	2.69
Dissociation Constants	pKa= 3.13
Collision Cross Section	146.16 Ų [M-H]-

Physical description & handling notes

• White solid; [Hawley] Slightly beige solid; [MSDSonline]
• WHITE CRYSTALLINE POWDER WITH CHARACTERISTIC ODOUR.
• White to light brown solid flakes, crystal powder or liquid.
• Plates from benzene or toluene
• White crystalline solid (pure compd)
• Colorless crystalline solid (pure)

GHS Hazard Classification

Reported hazard statements	H302, H315, H318, H400, H410, H312 (16.7%), H332 (16.7%), H411

Documented Uses

• Used as a post-emergence herbicide for control of annual and perennial broad leaved weeds in cereals, herbage seed crops, flax, rice, vines, peas, potatoes, asparagus, grassland, turf, orchards, roadsides, forestry, and aquatic areas; [HSDB]
• MCPA is used as a postemergence herbicide for control of broadleaf weeds in agricultural applications.
• HERBICIDE FOR CONTROL OF ANNUAL & PERENNIAL WEEDS
• Post-emergence control of annual and perennial broad leaved weeds (including thistles and docks) in cereals (alone or undersown), herbage seed crops, flax, rice, vines, peas, potatoes, asparagus, grassland, turf, under fruit trees, and on roadside verges and embankments. Control of broad-leaved and woody weeds in forestry. Control of aquatic broad leaved weeds.
• Dioxins occur as by-products from the manufacture of organochlorides, the bleaching of paper, chlorination by waste and drinking water treatment plants, municipal solid waste and industrial incinerators, and natural sources such as volcanoes and forest fires. (L177, L178)
• Herbicides, Transformation products

Synonyms

MCPA; 94-74-6; 2-METHYL-4-CHLOROPHENOXYACETIC ACID; (4-Chloro-2-methylphenoxy)acetic acid; Zelan; Mephanac; Emcepan; Netazol; Rhonox; Herbicide M; Hedarex M; Hedonal M; Okultin M; Leuna M; Bordermaster; Hornotuho

Frequently Asked Questions

What are the CAS number and molecular formula of 2-Methyl-4-chlorophenoxyacetic acid?

CAS 94-74-6; molecular formula C9H9ClO3; molecular weight — g/mol.

What other names is 2-Methyl-4-chlorophenoxyacetic acid known by?

MCPA, 94-74-6, 2-METHYL-4-CHLOROPHENOXYACETIC ACID, (4-Chloro-2-methylphenoxy)acetic acid, Zelan, Mephanac.

Is 2-Methyl-4-chlorophenoxyacetic acid classified as hazardous?

Hazard statements reported: H302, H315, H318, H400, H410.

What are the key physical properties of 2-Methyl-4-chlorophenoxyacetic acid?

Melting Point: 118-119 °C; Melting Point: 113-119 °C; Density: 1.56 @ 25 °C/15.5 °C; Vapor Pressure: 0.0000059 [mmHg].

Facts on this page are taken from PubChem (US National Library of Medicine) and Wikidata. Grade-specific data — assay, moisture, particle size, packaging, shelf life — is issued per batch on the COA and is not published here.