21739-92-4

Basic information

• Product Name: 5-Bromo-2-chlorobenzoic acid
• Synonyms: Benzoic acid, 5-bromo-2-chloro-;2-CHLORO-5-BROMOBENZOIC ACID;5-BROMO-2-CHLOROBENZOIC ACID;5-Bromo-2-chlorobenzoic acid, 98+%;5-Bromo-2-Chlorobenzoic Acid (BCBA);5-Bromo-2-chlorobenzoic acid ,99%;5-BROMO-2-CHLOROBENZOIC ACID FOR SYNTHES;5 - broMine - 2 - chlorobenzoic acid
• CAS NO: 21739-92-4
• Molecular Formula: C₇H₄BrClO₂
• Molecular Weight: 235.46
• EINECS: 244-558-5
• Product Categories: blocks;Bromides;Carboxes;Aromatic Carboxylic Acids, Amides, Anilides, Anhydrides & Salts;Benzoic acid;Organic acids;Miscellaneous;Acids & Esters;Bromine Compounds;Chlorine Compounds;C7;Carbonyl Compounds;Carboxylic Acids;Benzoic acid series;Building Blocks;Carbonyl Compounds;Carboxylic Acids;Chemical Synthesis;Organic Building Blocks
• Mol File: 21739-92-4.mol

Chemical Properties

• Melting Point: 154-156 °C(lit.)
• Boiling Point: 324.5 °C at 760 mmHg
• Flash Point: 150.1 °C
• Appearance: white to light yellow crystal powder
• Density: 1.7312 (rough estimate)
• Vapor Pressure: 0.0001mmHg at 25°C
• Refractive Index: 1.5590 (estimate)
• Storage Temp.: Store below +30°C.
• Solubility: 2.63g/l
• PKA: 2.49±0.25(Predicted)
• Water Solubility: Soluble in water 2.63 g/L @20°C.
• BRN: 2691432
• CAS DataBase Reference: 5-Bromo-2-chlorobenzoic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 5-Bromo-2-chlorobenzoic acid(21739-92-4)
• EPA Substance Registry System: 5-Bromo-2-chlorobenzoic acid(21739-92-4)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-37/39
• WGK Germany: 3
• HazardClass: IRRITANT
• Hazardous Substances Data: 21739-92-4(Hazardous Substances Data)

Usage

Uses

Used in Pharmaceutical Industry:
5-Bromo-2-chlorobenzoic acid is used as an intermediate in the synthesis of various pharmaceutical compounds. Its specific structural features make it a valuable building block for the development of new drugs with potential therapeutic applications.
Used in Chemical Analysis:
In the field of chemical analysis, 5-Bromo-2-chlorobenzoic acid is utilized to evaluate the homogeneity of organic powders. Its properties allow for accurate assessment and quality control of organic substances, ensuring the purity and consistency of materials used in various industries.
Used in Synthesis of Deuterated Compounds:
5-Bromo-2-chlorobenzoic acid is also used in the production of 2-chloro-5-deuteriobenzoic acid, a deuterated compound that has applications in the field of nuclear magnetic resonance (NMR) spectroscopy. Deuterated compounds are essential for studying molecular structures and interactions, as well as for developing new materials with specific properties.

InChI:InChI=1/C7H4BrClO2/c8-4-1-2-6(9)5(3-4)7(10)11/h1-3H,(H,10,11)/p-1

Synthetic route

2-chloro-5-bromobenzaldehyde (189628-37-3) → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
With C4H11FeMo6NO24(3-)*3C16H36N(1+); water; oxygen; sodium carbonate at 50℃; under 760.051 Torr; for 8h; Green chemistry;	99%
With 4H3N*4H(1+)*CuMo6O18(OH)6(4-); water; oxygen; sodium carbonate at 50℃; under 760.051 Torr; for 12h;	99%

tert-butyl 5-bromo-2-chloro-benzoate → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
In hexafluoropropan-2-ol at 100℃; for 2h; Microwave irradiation;	96%

2-chlorobenzotrichloride (2136-89-2) → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
Stage #1: 2-chlorobenzotrichloride With ferric(III) bromide; ferrocenyl methyl trimethyl ammonium bromide; copper(I) bromide; iron(II) bromide at 20℃; for 15h; Stage #2: With aminosulfonic acid In water at 80℃; for 8h;	92.5%
Stage #1: 2-chlorobenzotrichloride With bromine; iron for 6h; Stage #2: With sulfuric acid at 100℃; for 5h;	90%
Stage #1: 2-chlorobenzotrichloride With ferric(III) bromide; bromine In dichloromethane at 25 - 30℃; for 6h; Stage #2: With acetic acid at 110℃; for 15h; Reagent/catalyst; Temperature;

5-bromosalicyclic acid (89-55-4) → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
With tetrachloromethane; molybdenum hexacarbonyl In dimethyl sulfoxide at 150℃; for 6h; Reagent/catalyst; Solvent; Autoclave;	92.1%

5-bromo-2-chloro-benzoyl chloride (21900-52-7) → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
With oxalyl dichloride; N,N-dimethyl-formamide at 0 - 20℃; for 12h;	89.1%

ortho-chlorobenzoic acid (118-91-2) → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
Stage #1: ortho-chlorobenzoic acid With aluminum (III) chloride In chloroform for 0.5h; Large scale; Stage #2: With bromine In chloroform at 25℃; for 48.5h; Solvent; Large scale;	88%
With sodium periodate; sulfuric acid; sodium bromide In water; acetic acid at 30 - 65℃;	87.8%
Stage #1: ortho-chlorobenzoic acid With sodium sulfide; sulfuric acid at 30℃; for 0.333333h; Stage #2: With N-Bromosuccinimide at 30℃; for 0.166667h; Temperature; Reagent/catalyst;	85%

5-bromo-2-chlorobenzyl alcohol (149965-40-2) → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
With potassium phosphate; carbon dioxide; CrH6Mo6O24(3-)*3H3N*3H(1+) In dimethyl sulfoxide at 80℃; under 750.075 Torr; for 24h; Green chemistry;	80%

2-(2-chloro-5-bromophenyl)-4,5-dihydro-4,4-dimethyloxazole → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
With hydrogenchloride In water; acetonitrile at 60 - 70℃; for 3h; Time;	75.1%

bromochlorobenzene (106-39-8) + carbon dioxide (124-38-9) → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
With 2,2,6,6-tetramethyl-piperidine; n-butyllithium In tetrahydrofuran; hexane at -75℃; for 2h;	52%

bromochlorobenzene (106-39-8) + carbon dioxide (124-38-9) → 2-bromo-5-chlorobenzoic acid (21739-93-5) + 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
With lithium diisopropyl amide In tetrahydrofuran at -100℃;	A 20% B n/a

2-chloro-5-bromotoluene (54932-72-8) → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
With alkaline aqueous potassium permanganate solution
With nitric acid

5-Bromo-2-aminobenzoic acid (5794-88-7) → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
With hydrogenchloride; copper(l) chloride; sodium nitrite Diazotization.weiteres Reagens: wss. Salzsaeure;

2-chloro-benzoate silver → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
With bromine

2-methyl-4-nitro-benzenamine (99-52-5) → 5-bromo-2-chlorobenzoic acid (21739-92-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: man ersetzt die NH2-Gruppe durch Chlor, reduziert mit Zinn und Salzsaeure und ersetzt die neugebildete NH2-Gruppe durch Brom 2: HNO3 View Scheme

5-bromo-2-chlorobenzoic acid (21739-92-4) → 5-bromo-2-chloro-benzoyl chloride (21900-52-7)

Conditions	Yield
With oxalyl dichloride In DMF (N,N-dimethyl-formamide); dichloromethane at 20 - 25℃;	100%
With oxalyl dichloride; N,N-dimethyl-formamide In dichloromethane at 20℃; for 10h;	100%
With thionyl chloride In N,N-dimethyl-formamide; toluene at 0 - 100℃; for 4h; Inert atmosphere;	100%

5-bromo-2-chlorobenzoic acid (21739-92-4) + methylamine (74-89-5) → 5-bromo-2-chloro-N-methylbenzamide

Conditions	Yield
Stage #1: 5-bromo-2-chlorobenzoic acid With oxalyl dichloride; N,N-dimethyl-formamide In dichloromethane at 20℃; for 2h; Cooling with ice; Stage #2: methylamine With N-ethyl-N,N-diisopropylamine In tetrahydrofuran at 0 - 20℃; for 0.333333h;	100%

5-bromo-2-chlorobenzoic acid (21739-92-4) → 5-bromo-2-chlorobenzyl alcohol (149965-40-2)

Conditions	Yield
With dimethylsulfide; borane In tetrahydrofuran at 20℃; for 24h;	98%
With borane dimethyl sulfide complex In tetrahydrofuran at 0 - 23℃; for 14h;	98%
Stage #1: 5-bromo-2-chlorobenzoic acid With sodium tetrahydroborate; iodine In tetrahydrofuran for 18h; Reflux; Stage #2: With sodium hydrogensulfite In ethyl acetate	97%

methanol (67-56-1) + 5-bromo-2-chlorobenzoic acid (21739-92-4) → methyl 5-bromo-2-chloro-benzoate (251085-87-7)

Conditions	Yield
With sulfuric acid for 72h; Heating;	98%
With sulfuric acid for 72h; Heating / reflux;	98%
With hydrogenchloride In water	98%

fluorobenzene (462-06-6) + 5-bromo-2-chlorobenzoic acid (21739-92-4) → (2-chloro-5-bromophenyl)(4-fluorophenyl)methanone (915095-85-1)

Conditions	Yield
Stage #1: fluorobenzene; 5-bromo-2-chlorobenzoic acid With oxalyl dichloride; N,N-dimethyl-formamide at 0 - 25℃; Stage #2: With aluminum (III) chloride at 25℃;	96.94%
Stage #1: 5-bromo-2-chlorobenzoic acid With oxalyl dichloride In dichloromethane; N,N-dimethyl-formamide at 10 - 30℃; for 2h; Stage #2: fluorobenzene With aluminum (III) chloride at 75℃;	78%
Stage #1: 5-bromo-2-chlorobenzoic acid With thionyl chloride; N,N-dimethyl-formamide In dichloromethane at 39 - 42℃; Stage #2: fluorobenzene With aluminum (III) chloride In dichloromethane Reflux;	265 g

5-bromo-2-chlorobenzoic acid (21739-92-4) + 4-methoxy-benzylamine (2393-23-9) → 5-bromo-2-chloro-N-(4-methoxybenzyl)benzamide

Conditions	Yield
With silica gel In neat (no solvent) at 120℃; for 8h; Inert atmosphere; Sealed tube;	94%

2,2,2-trifluoroethanol (75-89-8) + 5-bromo-2-chlorobenzoic acid (21739-92-4) → 2,5-di-(2,2,2-trifluoroethoxy)benzoic acid (35480-52-5)

Conditions	Yield
With C10H12N2O8(4-)*Cu(2+)*2H4N(1+) In N,N-dimethyl-formamide at 20℃; for 4h; Reagent/catalyst;	93.5%
With potassium tert-butylate; copper(I) bromide In tetrahydrofuran; water	45%

ethanol (64-17-5) + 5-bromo-2-chlorobenzoic acid (21739-92-4) → 5-Bromo-2-chloro-benzoic acid ethyl ester (76008-73-6)

Conditions	Yield
With sulfuric acid In benzene Cooling with ice; Reflux;	92%
sulfuric acid
With sulfuric acid Reflux;
In N,N-dimethyl-formamide at 80℃; for 8h;

5-bromo-2-chlorobenzoic acid (21739-92-4) + benzylamine (100-46-9) → N-benzyl-5-bromo-2-chlorobenzamide

Conditions	Yield
With silica gel In neat (no solvent) at 120℃; for 8h; Inert atmosphere; Sealed tube;	92%

5-bromo-2-chlorobenzoic acid (21739-92-4) + C8H12O → (5-bromo-2-chlorophenyl)(4-ethyloxyphenyl)methanone (461432-22-4)

Conditions	Yield
Stage #1: 5-bromo-2-chlorobenzoic acid; C8H12O With oxalyl dichloride In dichloromethane; N,N-dimethyl-formamide at 10 - 30℃; Stage #2: With aluminum (III) chloride In dichloromethane for 1h; Cooling with ice;	92%

oxalyl dichloride (79-37-8) + 5-bromo-2-chlorobenzoic acid (21739-92-4) → methyl 5-bromo-2-chloro-benzoate (251085-87-7)

Conditions	Yield
In methanol; dichloromethane; N,N-dimethyl-formamide	91%

5-bromo-2-chlorobenzoic acid (21739-92-4) + Phenetole (103-73-1) → (5-bromo-2-chlorophenyl)(4-ethyloxyphenyl)methanone (461432-22-4)

Conditions	Yield
With dipotassium peroxodisulfate; phosphorus; iron(III) oxide; sodium carbonate; sodium bromide In 1,4-dioxane at 40℃; Temperature; Solvent; Molecular sieve;	90%
Stage #1: 5-bromo-2-chlorobenzoic acid With oxalyl dichloride; N,N-dimethyl-formamide In dichloromethane for 3h; Stage #2: Phenetole With aluminum (III) chloride In dichloromethane at 4 - 5℃; for 1h;	70%
Stage #1: 5-bromo-2-chlorobenzoic acid With oxalyl dichloride; N,N-dimethyl-formamide In dichloromethane at 20℃; Stage #2: Phenetole With aluminum (III) chloride In dichloromethane at 20℃; for 2h; Cooling with ice;

5-bromo-2-chlorobenzoic acid (21739-92-4) → 2-chloro-5-deuteriobenzoic acid (121990-18-9)

Conditions	Yield
With Raney Cu-Al alloy; sodium carbonate In water-d2 at 65℃; for 8h;	88%

5-bromo-2-chlorobenzoic acid (21739-92-4) + phenol (108-95-2) → (5-bromo-2-chlorophenyl)(4-hydroxyphenyl)methanone (1360568-68-8)

Conditions	Yield
With polyphosphoric acid at 50 - 85℃;	87%

norepinephrine (48115-38-4) + 5-bromo-2-chlorobenzoic acid (21739-92-4) → 5-bromo-2-chloro-N-(1-hydroxy-1-phenylpropane-2-yl)benzamide (1150313-65-7)

Conditions	Yield
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine In N,N-dimethyl-formamide at 0 - 20℃;	86%

5-bromo-2-chlorobenzoic acid (21739-92-4) + 4-methoxy-aniline (104-94-9) → N-(4-methoxyphenyl)-4-bromoanthranilic acid

Conditions	Yield
With copper(I) oxide; copper; potassium carbonate In 2-ethoxy-ethanol at 130℃; for 24h;	85%

5-bromo-2-chlorobenzoic acid (21739-92-4) + tert-butyl alcohol (75-65-0) → tert-butyl (5-bromo-2-chlorophenyl)carbamate (740806-51-3)

Conditions	Yield
With diphenyl phosphoryl azide; triethylamine for 3h; Heating / reflux;	85%

5-bromo-2-chlorobenzoic acid (21739-92-4) + N,O-dimethylhydroxylamine*hydrochloride (6638-79-5) → 5-bromo-2-chloro-N-methoxy-N-methyl-benzamide (842136-59-8)

Conditions	Yield
With N-ethyl-N,N-diisopropylamine; HATU In N,N-dimethyl-formamide at 20℃; for 14h;	84%
With N-ethyl-N,N-diisopropylamine; HATU In N,N-dimethyl-formamide at 20℃; for 14h;	84%
With N-ethyl-N,N-diisopropylamine; N-[(dimethylamino)-3-oxo-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl-methylene]-N-methylmethanaminium hexafluorophosphate In N,N-dimethyl-formamide at 20℃; for 16h;	82%
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine In dichloromethane at 20℃; for 64h;
With diethylamine; dicyclohexyl-carbodiimide In dichloromethane at 5 - 10℃; for 0.5h;	88 g

5-bromo-2-chlorobenzoic acid (21739-92-4) + phenethylamine (64-04-0) → 5-bromo-N-phenethylanthranilic acid (1002965-88-9)

Conditions	Yield
With copper(I) oxide; copper; potassium carbonate In various solvent(s) at 130℃; for 24h;	84%

5-bromo-2-chlorobenzoic acid (21739-92-4) + 1-amino-2-propene (107-11-9) → N-allyl-5-bromo-2-chlorobenzamide

Conditions	Yield
Stage #1: 5-bromo-2-chlorobenzoic acid With thionyl chloride for 1h; Reflux; Stage #2: 1-amino-2-propene In dichloromethane at 20℃; for 2h;	83%
With silica gel In neat (no solvent) at 120℃; for 14h; Inert atmosphere; Sealed tube;	80%

5-bromo-2-chlorobenzoic acid (21739-92-4) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → 2-chloro-5-formylbenzoic acid (1206625-81-1)

Conditions	Yield
Stage #1: 5-bromo-2-chlorobenzoic acid With isopropylmagnesium chloride In tetrahydrofuran at -45 - 20℃; for 16.5h; Inert atmosphere; Stage #2: N,N-dimethyl-formamide In tetrahydrofuran at 0 - 20℃; for 1.83333h; Inert atmosphere; Stage #3: With hydrogenchloride In tetrahydrofuran; water at 20 - 37℃; for 1.58333h; Inert atmosphere;	80%
Stage #1: 5-bromo-2-chlorobenzoic acid With isopropylmagnesium chloride In tetrahydrofuran at -30 - 20℃; Bouveault aldehyde synthesis; Inert atmosphere; Large scale reaction; Stage #2: N,N-dimethyl-formamide In tetrahydrofuran at 0℃; Bouveault aldehyde synthesis; Inert atmosphere; Large scale reaction; Stage #3: With hydrogenchloride In tetrahydrofuran; water at 10 - 20℃; Bouveault aldehyde synthesis; Large scale reaction;	80%

1-(aminomethyl)cycloheptanol (45732-95-4) + 5-bromo-2-chlorobenzoic acid (21739-92-4) → C15H19BrClNO2 (1227807-64-8)

Conditions	Yield
With O-(1H-benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate; N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 20℃; for 1h;	80%

5-bromo-2-chlorobenzoic acid (21739-92-4) + aniline (62-53-3) → 5-Bromo-N-phenylanthranilic acid (82762-60-5)

Conditions	Yield
With potassium carbonate; CuPy2Cl2 at 75℃; for 0.333333h; microwave irradiation;	79%

Upstream product

• 54932-72-8 2-chloro-5-bromotoluene 
• 5794-88-7 5-Bromo-2-aminobenzoic acid 
• 118-91-2 ortho-chlorobenzoic acid 
• 106-39-8 bromochlorobenzene 
• 124-38-9 carbon dioxide 
• 99-52-5 2-methyl-4-nitro-benzenamine 
• 503555-23-5 tert-butyl 5-bromo-2-chloro-benzoate 
• 2136-89-2 2-chlorobenzotrichloride 
• 189628-37-3 2-chloro-5-bromobenzaldehyde 
• 89-55-4 5-bromosalicyclic acid 
• 21900-52-7 5-bromo-2-chloro-benzoyl chloride 
• 149965-40-2 5-bromo-2-chlorobenzyl alcohol 
• 57381-44-9 5-bromo-2-chlorobenzonitrile 

Downstream Products

• 21900-52-7 5-bromo-2-chloro-benzoyl chloride 
• 728931-56-4 5-bromo-2-(4-bromo-anilino)-benzoic acid 
• 76008-73-6 5-Bromo-2-chloro-benzoic acid ethyl ester 
• 121990-18-9 2-chloro-5-deuteriobenzoic acid 
• 118-91-2 ortho-chlorobenzoic acid 
• 149965-40-2 5-bromo-2-chlorobenzyl alcohol 
• 873914-47-7 N-(4-methoxyphenyl)-4-bromoanthranilic acid 
• 842136-59-8 5-bromo-2-chloro-N-methoxy-N-methyl-benzamide 
• 89-55-4 5-bromosalicyclic acid 
• 251085-87-7 methyl 5-bromo-2-chloro-benzoate 
• 914106-40-4 5-bromo-2-chlorobenzaldoxime 
• 914106-04-0 5-bromo-2-chlorobenzaldehyde chlorooxime 
• 914106-15-3 3-(5-bromo-2-chlorophenyl)-5-(4-cyanophenyl)isoxazole 
• 914105-96-7 3-(2-chloro-5-cyanophenyl)-5-(4-cyanophenyl)isoxazole 

Relevant articles and documents

An efficient chromium(iii)-catalyzed aerobic oxidation of methylarenes in water for the green preparation of corresponding acids

A highly efficient method to oxidize methylarenes to their corresponding acids with a reusable Cr catalyst was developed. The reaction can be carried out in water with 1 atm oxygen and K2S2O8as cooxidants, proceeds under green and mild conditions, and is suitable for the oxidation of both electron-deficient and electron-rich methylarenes, including heteroaryl methylarenes, even at the gram level. The excellent result, together with its simplicity of operation and the ability to continuously reuse the catalyst, makes this new methodology environmentally benign and cost-effective. The generality of this methodology gives it the potential for use on an industrial scale. Differing from the accepted oxidation mechanism of toluene, GC-MS studies and DFT calculations have revealed that the key benzyl alcohol intermediate is formed under the synergetic effect of the chromium and molybdenum in the Cr catalyst, which can be further oxidized to afford benzaldehyde and finally benzoic acid.

Preparation method of high-selectivity 5-bromo-2-chlorobenzoic acid

The invention provides a novel method for preparing 5-bromine-2-chlorobenzoic acid with high selectivity, and particularly relates to a method for preparing 5-bromine-2-chlorobenzoic acid with high selectivity by taking dibrominated amino silica gel as a brominating reagent, iron trifluoromethanesulfonate as a catalyst and halogenated hydrocarbon as a solvent. According to the novel method, dibrominated amino silica gel can be recycled, wherein the 6-time recovery rate reaches 98%; and the method is environment-friendly in process, simple and convenient to operate, low in EHS risk, high in product yield (more than or equal to 95%) and good in quality (more than or equal to 99.8%), is a process suitable for industrial production, greatly reduces the production cost of 5-bromo-2-chlorobenzoic acid, and remarkably reduces environmental pollution and resource consumption in the production process.

Preparation method 5 - bromo -2 -chlorobenzoic acid

The invention provides a preparation method of 5 -bromo -2 -chlorobenzoic acid, which comprises (1) contacting 2 - chlorobenzonitrile with a bromination reagent for bromination reaction to obtain 5 - bromo -2 - chlorobenzonitrile. (2) Hydrolysis of 5 - bromo -2 - chlorobenzonitrile in the presence of a base to give 5 - bromo -2 -chlorobenzoate. The 5 - bromo -2 -chlorobenzoate is then contacted with a protic acid to give 5 - bromo -2 -chlorobenzoic acid. The preparation method has the advantages of simple process, high safety, cheap and accessible raw materials, low cost and 5 - bromo -2 - chlorobenzoic acid yield, high purity and the like.

Preparation method of 5-bromo-2-chlorobenzoic acid

The invention relates to a preparation method of 5-bromo-2-chlorobenzoic acid. The preparation method comprises the following steps: taking 2-chlorobenzoic acid as an initial reactant, sequentially carrying out chlorination, acylation and cyclization reactions to obtain a protective group o-chlorobenzoic acid (a compound represented by formula III), and sequentially carrying out bromination and hydrolysis to obtain 5-bromo-2-chlorobenzoic acid. The reaction conditions are mild, and the safety of the preparation process is improved. The yield of the prepared product can reach 75% or above, thepurity can reach 99% or above, and the purity and yield are much higher than those of an existing preparation method. Meanwhile, the preparation method is simple in process step, the product is easy to purify, 5-bromo-2-chlorobenzoic acid can be synthesized on a large scale, and the preparation method has a good industrial development prospect.

Highly efficient oxidation of alcohols to carboxylic acids using a polyoxometalate-supported chromium(iii) catalyst and CO2

Direct catalytic oxidation of alcohols to carboxylic acids is very attractive, but economical catalysis systems have not yet been well established. Here, we show that a pure inorganic ligand-supported chromium compound, (NH4)3[CrMo6O18(OH)6] (simplified as CrMo6), could be used to effectively promote this type of reaction in the presence of CO2. In almost all cases, oxidation of various alcohols (aromatic and aliphatic) could be achieved under mild conditions, and the corresponding carboxylic acids can be achieved in high yield. The chromium catalyst 1 can be reused several times with little loss of activity. Mechanism study and control reactions demonstrate that the acidification proceeds via the key oxidative immediate of aldehydes.

Preparation method of 5-bromo-2-chlorobenzoic acid

The invention relates to a preparation method of 5-bromo-2-chlorobenzoic acid, which is characterized by comprising the following steps: reacting 2-chlorobenzotrichloride used as a raw material with abromination reagent under the catalytic action of a first catalyst to generate 2-chloro-5-bromobenzotrichloride, adding water and a hydrolysis catalyst into the 2-chloro-5-bromobenzotrichloride, andcarrying out after-treatment and purification to obtain 5-bromo-2-chlorobenzoic acid, wherein the first catalyst is prepared by compounding iron bromide, ferrous bromide, copper bromide, (ferrocene methyl) trimethyl ammonium bromide and brominated ferrocene. The invention further discloses the 5-bromine-2-chlorobenzoic acid prepared according to the preparation method of the 5-bromine-2-chlorobenzoic acid. According to the preparation method of 5-bromine-2-chlorobenzoic acid disclosed by the invention, the traditional preparation process conditions are optimized and innovated, so that the product purity, the reaction conversion rate and the production efficiency are effectively improved, the preparation cost is low, the environmental pressure is low, the synthesis route is short, the operation is simple and feasible, the emission of three wastes is reduced, and the reaction yield is high.

Preparation method of 5-bromo-2-chlorobenzoic acid

The invention relates to the technical field of preparation of 5-bromo-2-chlorobenzoic acid, and in particular relates to a preparation method of the 5-bromo-2-chlorobenzoic acid. The preparation method of the 5-bromo-2-chlorobenzoic acid provided by the invention comprises the following steps: mixing 2-chlorobenzoic acid, bromine, a catalyst and an organic solvent, and performing a bromination reaction to obtain the 5-bromo-2-chlorobenzoic acid. The preparation method provided by the invention has short steps, mild reaction conditions, low costs, a high yield, and high purity of the product;and at the same time, according to the description of embodiments, the purity by HPLC of the 5-bromo-2-chlorobenzoic acid prepared by using the preparation method is >=99.5%, and the molar yield is >=80.9%.

Preparation method of high-selectivity 5-bromo-2-chlorobenzoic acid

The invention discloses a preparation method of 5-bromo-2-chlorobenzoic acid and belongs to the technical field of organic synthesis. According to the preparation method, 2-chlorobenzoic acid is takenas a raw material and is subjected to a mono-bromination reaction in an NBS/sulfuric acid system, 5-bromo-2-chlorobenzoic acid is prepared, and a catalyst inhibiting production of 4-bromo-2-chlorobenzoic acid is added in the reaction process. The process is simple, raw materials are cheap and easy to obtain, the cost is low, the yield is high, and the high-purity 5-bromo-2-chlorobenzoic acid product is obtained through one-time refining after the reaction; the catalyst can effectively inhibit production of impurities such as 4-bromo-2-chlorobenzoic acid and the like, and the impurity contentof the obtained product is low.

Synthesis method of 2-halo-5-bromobenzoic acid

The invention discloses a synthesis method of 2-halo-5-bromobenzoic acid. The method comprises the following steps of under the action of sulfuric acid, carrying out a bromination reaction on o-halo-benzoic acid and NBS in an organic solvent, and after the reaction is finished, carrying out posttreatment to obtain 2-halo-5-bromobenzoic acid. The method has the advantages of being short in reactionroute, simple in operation, environmentally friendly, safe and economical and has a broad application prospect.

Preparation method of 2,5-dihalo-benzoic acid

The invention discloses a preparation method of 2,5-dihalo-benzoic acid. The method comprises the following steps: concentrated sulfuric acid is added dropwise to a mixed solution containing sodium bromide, periodate and 2-halo-benzoic acid in presence of water and acetic acid, the mixed solution is subjected to a reaction, and 2,5-dihalo-benzoic acid is prepared. The problems of long time neededfor preparation, high reaction temperature and the like of the preparation method of 2,5-dihalo-benzoic acid in the prior art can be solved.