150-68-5 Usage
Description
MONURON, also known as monuron, is a white crystalline solid or white powder with a slight odor. It has a melting point of 175°C and is classified as moderately toxic by ingestion. MONURON is a member of the class of ureas, specifically urea in which one of the nitrogens is substituted by a p-chlorophenyl group while the other is substituted by two methyl groups. It is characterized by its very low solubility in water and hydrocarbon solvents, slight solubility in oils, partial solubility in alcohols, and stability toward oxidation and moisture.
Uses
Used in Agriculture:
MONURON is used as a herbicide for controlling the growth of unwanted plants in agricultural fields. Its application helps to improve crop yield by reducing competition for resources such as nutrients, water, and sunlight.
Used as a Sugarcane-Flowering Suppressant:
In the sugarcane industry, MONURON is utilized as a flowering suppressant to prevent the plants from flowering prematurely. This is important because flowering can lead to a reduction in sugar content and overall yield of the sugarcane crop.
Used in Analytical Chemistry:
MONURON may be used as a reference standard in the determination of monuron levels in rice and corn using high-performance liquid chromatography coupled with fluorescence detection combined with ultraviolet decomposition and post-column derivatization. This application helps to ensure the quality and safety of these staple crops by monitoring the presence of MONURON residues.
Air & Water Reactions
Insoluble in water. Is hydrolyzed slowly by acids and alkalis, and more rapidly on heating .
Reactivity Profile
MONURON is a chlorinated urea derivative. May react with azo and diazo compounds to generate toxic gases. May react with strong reducing agents to generate flammable gases. Reacts as a weak base. Combustion generates mixed oxides of nitrogen (NOx).
Hazard
Questionable carcinogen.
Health Hazard
Toxic properties are similar to Diuron; hydro-lyzes under acidic or alkaline conditions top-chloroaniline, which can cause anemia andmethemoglobinemia; LD50 data published inthe literature differ; acute and chronic tox-icity of this herbicide is probably of loworder; no reported case of human poisoning; showed clear evidence of carcinogenicity in male F344/N rats fed diets containing 750 ppm monuron for 2 years; causedcancers in the kidney and liver (NationalToxicology Program 1988); female rats andmale and female mice (B6C3F1) showed noevidence; induced cytomegaly of the renalepithelial cells in rats.LD50 oral (rat): 3700 mg/kg (Bailey andWhite, 1965)LD50 oral (rat): 1053 mg/kg (Lewis 1995).
Fire Hazard
Flash point data for MONURON are not available; however, MONURON is probably combustible.
Flammability and Explosibility
Notclassified
Safety Profile
Moderately toxic by
ingestion, intraperitoneal, and possibly other
routes. Experimental teratogenic and
reproductive effects. Questionable
carcinogen with experimental carcinogenic
data. Mutation data reported. An herbicide.
When heated to decomposition it emits very
toxic fumes of NOx and Cl-.
Environmental Fate
Biological. Monuron was mineralized in sewage samples obtained from a water treatment
plant in Ithica, NY. (4-Chlorophenyl)urea and 4-chloroaniline were tentatively identified
as metabolites (Wang et al., 1985).Soil/Plant. In soils and plants, monuron is demethylated at the terminal nitrogen atom
coupled with ring hydroxylation forming 3-(2-hydroxy-4-chlorophenyl)urea and 3-(3-
hydroxy-4-chlorophenyl)urea (Hartley and Kidd, 1987). Walln?efer et al. (197Photolytic. When an aqueous solution of monuron was exposed to sunlight or simulated
sunlight, the major degradative pathways observed were the photooxidation and demethylation
of the N-methyl groups (Crosby and Tang, 1969; Tanaka et al., 1982a),Tanaka et al. (1981) studied the photolysis of monuron in dilute aqueous solutions in
order to fully characterize a substituted diphenylamine that was observed in an earlier
investigation (Tanaka et al., 1977). They identified this compound as an isomeric mixture
containing 92% 2-chloro-4¢,5-bis(N¢,N¢-dimethylureido)biphenyl and 8% 5-chloro-2,4¢-
bis(N¢,N¢-dimethylureido)biphenyl (Tanaka et al., 1981).Tanaka et al. (1982) undertook a study to identify the several biphenyls formed in
earlier photolysis studies (Tanaka et al., 1979, 1981). They identified these compounds as
2,4¢-, 3,4¢- and 4,4¢-bis-(N¢,N¢-dimethylureido)biphenyls (fenuron biphenyls) (Ta
Purification Methods
Crystallise monuron from MeOH. [Beilstein 12 IV 1191.]
Check Digit Verification of cas no
The CAS Registry Mumber 150-68-5 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 1,5 and 0 respectively; the second part has 2 digits, 6 and 8 respectively.
Calculate Digit Verification of CAS Registry Number 150-68:
(5*1)+(4*5)+(3*0)+(2*6)+(1*8)=45
45 % 10 = 5
So 150-68-5 is a valid CAS Registry Number.
150-68-5Relevant articles and documents
3-(p-Chlorophenyl)-1,1-dimethylurea; a new herbicide.
BUCHA,TODD
, p. 493 - 494 (1951)
-
Hydroamination and Hydrophosphination of Isocyanates/Isothiocyanates under Catalyst-Free Conditions
Zhu, Xiancui,Xu, Mengchen,Sun, Jinrong,Guo, Dianjun,Zhang, Yiwei,Zhou, Shuangliu,Wang, Shaowu
, p. 5213 - 5218 (2021/10/19)
Symmetrical and unsymmetrical N,N’-disubstituted as well as trisubstituted ureas/thioureas by the hydroamination of isocyanates/isothiocyanates, and various phosphathioureas by the hydrophosphination of isothiocyanates have been synthesized in good to excellent yields under catalyst-free and mild conditions. This protocol is also applicable for the efficient synthesis of chiral ureas and thioureas and common herbicides, such as fenuron and monuron.
One-pot synthesis of 2,3-difunctionalized indoles: Via Rh(III)-catalyzed carbenoid insertion C-H activation/cyclization
Lv, Honggui,Shi, Jingjing,Wu, Bo,Guo, Yujuan,Huang, Junjun,Yi, Wei
supporting information, p. 8054 - 8058 (2017/10/13)
Reported herein is the first Rh(iii)-catalyzed carbenoid insertion C-H activation/cyclization of N-arylureas and α-diazo β-keto esters. The redox-neutral reaction has the following features: good to excellent yields, broad substrate/functional group tolerance, exclusive regioselectivity, and no need for additional oxidants or additives, which render this methodology as a more efficient and versatile alternative to the existing methods for the synthesis of 2,3-difunctionalized indoles.