50-84-0 Usage
Description
2,4-Dichlorobenzoic acid is a di-halogenated benzoic acid derivative, characterized by its white to slightly yellowish powder appearance. It is defined as a chlorobenzoic acid in which the ring hydrogens at positions 2 and 4 are substituted by chloro groups. This chemical compound serves as an intermediate in the synthesis of various compounds and has found applications in different industries.
Uses
Used in Pesticide Synthesis:
2,4-Dichlorobenzoic acid is used as an intermediate in the synthesis of spirodiclofen (S682990), a tetronic acid acaricide fungicide. This fungicide is specifically utilized in controlling red mites, which are agricultural pests that can cause significant damage to crops.
Used in Pharmaceutical Synthesis:
2,4-Dichlorobenzoic acid is used as a reagent during the synthesis of pyrimido[2?,1':2,3]thiazolo[4,5-b]quinoxaline derivatives. These derivatives have potential applications in the pharmaceutical industry, possibly due to their biological activities or properties.
Used in Organic Chemistry:
As a starting reagent, 2,4-dichlorobenzoic acid is employed in the synthesis of 1-(substituted)-1,4-dihydro-6-nitro-4-oxo-7-(sub-secondary amino)-quinoline-3-carboxylic acids. These complex organic compounds may have various applications in research and development, particularly in the fields of medicinal chemistry and drug discovery.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
2,4-Dichlorobenzoic acid is a halogenated carboxylic acid. Carboxylic acids donate hydrogen ions if a base is present to accept them. They react in this way with all bases, both organic (for example, the amines) and inorganic. Their reactions with bases, called "neutralizations", are accompanied by the evolution of substantial amounts of heat. Neutralization between an acid and a base produces water plus a salt. Carboxylic acids with six or fewer carbon atoms are freely or moderately soluble in water; those with more than six carbons are slightly soluble in water. Soluble carboxylic acid dissociate to an extent in water to yield hydrogen ions. The pH of solutions of carboxylic acids is therefore less than 7.0. Many insoluble carboxylic acids react rapidly with aqueous solutions containing a chemical base and dissolve as the neutralization generates a soluble salt. Carboxylic acids in aqueous solution and liquid or molten carboxylic acids can react with active metals to form gaseous hydrogen and a metal salt. Such reactions occur in principle for solid carboxylic acids as well, but are slow if the solid acid remains dry. Even "insoluble" carboxylic acids may absorb enough water from the air and dissolve sufficiently in 2,4-Dichlorobenzoic acid to corrode or dissolve iron, steel, and aluminum parts and containers. Carboxylic acids, like other acids, react with cyanide salts to generate gaseous hydrogen cyanide. The reaction is slower for dry, solid carboxylic acids. Insoluble carboxylic acids react with solutions of cyanides to cause the release of gaseous hydrogen cyanide. Flammable and/or toxic gases and heat are generated by the reaction of carboxylic acids with diazo compounds, dithiocarbamates, isocyanates, mercaptans, nitrides, and sulfides. Carboxylic acids, especially in aqueous solution, also react with sulfites, nitrites, thiosulfates (to give H2S and SO3), dithionites (SO2), to generate flammable and/or toxic gases and heat. Their reaction with carbonates and bicarbonates generates a harmless gas (carbon dioxide) but still heat. Like other organic compounds, carboxylic acids can be oxidized by strong oxidizing agents and reduced by strong reducing agents. These reactions generate heat. A wide variety of products is possible. Like other acids, carboxylic acids may initiate polymerization reactions; like other acids, they often catalyze (increase the rate of) chemical reactions.
Fire Hazard
Flash point data for 2,4-Dichlorobenzoic acid are not available; however, 2,4-Dichlorobenzoic acid is probably combustible.
Purification Methods
Crystallise the acid from aqueous EtOH (charcoal), then *benzene (charcoal). It can also be recrystallised from water. [Beilstein 9 IV 998.] It can be freed from isomeric acids (to <0.05%) via the (±)--methylbenzylamine salt as follows: dissolve the dichloro-acid (10g, 50.2mmol) in isopropanol (200mL), heat to 60o and add the (±)-benzylamine (5.49g, 45.3mmol), then stir it at 60o for 1hour. Cool the mixture to room temperature, filter the slurry, wash it with isopropanol (25mL) and dry it in vacuo at 40o overnight to give 79% of the salt with m 185.2o. Dissolve the salt (5g) in H2O (50mL) and MeOH (20mL), then heat to 60o and add concentrated HCl to pH <2.0. Cool the solution to room temperature add H2O (12mL), filter it, wash it with H2O (30mL) and dry it in vacuo at 40o overnight to give 94% of the acid with m 162.0o. [Ley & Yates Organic Process Research & Development 12 120 2008.]
Check Digit Verification of cas no
The CAS Registry Mumber 50-84-0 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 5 and 0 respectively; the second part has 2 digits, 8 and 4 respectively.
Calculate Digit Verification of CAS Registry Number 50-84:
(4*5)+(3*0)+(2*8)+(1*4)=40
40 % 10 = 0
So 50-84-0 is a valid CAS Registry Number.
InChI:InChI=1/C7H4Cl2O2/c8-4-1-2-5(7(10)11)6(9)3-4/h1-3H,(H,10,11)/p-1
50-84-0Relevant articles and documents
Purification of 2,4 dichlorobenzoic acid
Ley, Christopher P.,Yates, Matthew H.
, p. 120 - 124 (2008)
A practical and efficient method to purify 2,4-dichlorobenzoic acid is described. The formation of an α-methylbenzylamine salt reduces the levels of positional isomer impurities to 0.05%. Although this purification method is not universal for all substituted benzoic acids, it was shown to be applicable to several other benzoic acids.
Selective Solvent-Free and Additive-Free Oxidation of Primary Benzylic C–H Bonds with O2 Catalyzed by the Combination of Metalloporphyrin with N-Hydroxyphthalimide
Shen, Hai-Min,Qi, Bei,Hu, Meng-Yun,Liu, Lei,Ye, Hong-Liang,She, Yuan-Bin
, p. 3096 - 3111 (2020/04/29)
Abstract: A protocol for solvent-free and additive-free oxidation of primary benzylic C–H bonds with O2 was presented through adjusting the combination of metalloporphyrins and NHPI as binary catalysts to overcome the deficiencies encountered in current oxidation systems. The effects of reaction temperature, porphyrin structure, central metal, catalyst loading and O2 pressure were investigated systematically. For the optimized combination of T(2-OCH3)PPCo and NHPI, all the primary benzylic C–H bonds could be functionalized efficiently and selectively at 120 °C and 1.0?MPa O2 with aromatic acids as the primary products. The selectivity towards aromatic acids could reach up to 70–95% in the conversion of more than 30% for most of the substrates possessing primary benzylic C–H bonds in the metalloporphyrin loading of 0.012% (mol/mol). And the superior performance of T(2-OCH3)PPCo among the metalloporphyrins investigated was mainly attributed to its high efficiency in charge transfer and fewer positive charges around central metal Co (II) which favored the adduction of O2 to cobalt (II) forming the high-valence metal-oxo complex followed by the production of phthalimide N-oxyl radical (PINO) and the initiation of the catalytic oxidation cycle. This work would provide not only an efficient protocol in utilization of hydrocarbons containing primary benzylic C–H bonds, but also a significant reference in the construction of more efficient C–H bonds oxidation systems. Graphic Abstract: The solvent-free and additive-free oxidation of primary benzylic C–H bonds with O2 was presented through adjusting the combination of metalloporphyrins and NHPI as binary catalysts, and the highest selectivity towards aromatic acid reached up to 95.1% with the conversion of 88.5% in the optimized combination of T(2-OCH3)PPCo and NHPI.[Figure not available: see fulltext.].
Copper (II) immobilized on magnetically separable L-arginine-β-cyclodextrin ligand system as a robust and green catalyst for direct oxidation of primary alcohols and benzyl halides to acids in neat conditions
Nejad, Masoumeh Jadidi,Salamatmanesh, Arefe,Heydari, Akbar
, (2020/02/11)
Copper (II) immobilized on L-arginine-β-cyclodextrin-functionalized magnetite nanoparticles (nano-Fe3O4@L-arginine-CD-Cu(II)) were successfully synthesized and fully characterized using FT-IR, XRD, SEM, EDX, ICP, TGA and VSM techniques. The catalytic activity of these magnetically retrievable nanoparticles was evaluated in the direct oxidation of primary alcohols and benzyl halides to acids in neat conditions that was observed to proceed well and products were obtained in good yields. In addition to showing good catalytic activity, the magnetic catalyst is easy to synthesize and can be recycled at least five times with little loss in activity.
