2516-96-3

Basic information

• Product Name: 2-Chloro-5-nitrobenzoic acid
• Synonyms: RARECHEM AL BO 0234;2-CHLORO-5-NITROBENZOIC ACID;5-NITRO-2-CHLOROBENZOIC ACID;LABOTEST-BB LT00847209;2-chloro-5-nitro-benzoicaci;6-Chloro-3-nitrobenzoic acid;Benzoic acid, 2-chloro-5-nitro-;2-Chloro-5-nirtrobenzoic acid
• CAS NO: 2516-96-3
• Molecular Formula: C₇H₄ClNO₄
• Molecular Weight: 201.56
• EINECS: 219-739-7
• Product Categories: Acids and Derivatives;Aromatic Carboxylic Acids, Amides, Anilides, Anhydrides & Salts;Organic acids;Miscellaneous;C7;Carbonyl Compounds;Carboxylic Acids
• Mol File: 2516-96-3.mol
• Article Data: 13

Chemical Properties

• Melting Point: 165-168 °C(lit.)
• Boiling Point: 356.5 °C at 760 mmHg
• Flash Point: >100°C
• Appearance: Light yellow to beige-brown/Crystalline Powder
• Density: 1.6
• Vapor Pressure: 1.06E-05mmHg at 25°C
• Refractive Index: 1.6000 (estimate)
• Storage Temp.: Store below +30°C.
• Solubility: 3.6g/l
• PKA: pK1: 2.17 (25°C)
• BRN: 1877474
• CAS DataBase Reference: 2-Chloro-5-nitrobenzoic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 2-Chloro-5-nitrobenzoic acid(2516-96-3)
• EPA Substance Registry System: 2-Chloro-5-nitrobenzoic acid(2516-96-3)

Safety Data

• Hazard Codes: Xn,N,Xi
• Statements: 22-37/38-41-50-36/37/38
• Safety Statements: 26-39-61-24/25-36
• RIDADR: UN3077 9/PG 3
• WGK Germany: 1
• TSCA: Yes
• Hazardous Substances Data: 2516-96-3(Hazardous Substances Data)

Usage

Chemical Properties

light yellow to light yellow-green crystalline

General Description

2-Chloro-5-nitrobenzoic acid undergoes microwave-assisted, regioselective amination reaction with aliphatic and aromatic amines to yield N-substituted 5-nitroanthranilic acid derivatives. It acts as ligand and forms a red luminescent one dimensional coordination polymer with Eu(III).

InChI:InChI=1/C7H4ClNO4/c8-6-2-1-4(9(12)13)3-5(6)7(10)11/h1-3H,(H,10,11)/p-1

Synthetic route

ortho-chlorobenzoic acid (118-91-2) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
With sulfuric acid; nitric acid at -5 - 20℃; for 2h; Large scale;	95.4%
With sulfuric acid; nitric acid at -5 - 5℃; for 2h;	95.8%
With sulfuric acid; potassium nitrate at 25℃; for 3h;	90.2%

1-chloro-4-nitro-2-(trichloromethyl)benzene (831-50-5) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
With sulfuric acid In water at 65 - 95℃; for 3h; Temperature;	95%

2-chloro-5-nitro-benzamide (16588-15-1) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
With hydrogenchloride
With sulfuric acid; sodium nitrite

1-chloro-2-methyl-4-nitrobenzene (13290-74-9) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
With nitric acid at 140 - 150℃;

5-nitrosalicylic acid (96-97-9) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
With phosphorus pentachloride

2-chloro-5-nitrobenzaldehyde (6361-21-3) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
With permanganate(VII) ion

ortho-chlorobenzoic acid (118-91-2) → 2-chloro-5-nitrobenzoic acid (2516-96-3) + 2-chloro-3-nitrobezoic acid (3970-35-2)

Conditions	Yield
With nitric acid
With sulfuric acid; nitric acid

2-chloro-N-(4-chlorophenyl)-5-nitrobenzamide (54253-05-3) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
With sodium hydroxide

hydrogenchloride (7647-01-0) + 6-nitro-3-phenylbenzo[d][1,2,3]triazin-4(3H)-one (60041-99-8) → 2-chloro-5-nitrobenzoic acid (2516-96-3) + aniline (62-53-3)

Conditions	Yield
at 120 - 130℃;

hydrogenchloride (7647-01-0) + 6-nitrobenzo[d][1,2,3]triazin-4(3H)-one (91532-29-5) → 2-chloro-5-nitrobenzoic acid (2516-96-3) + ammonia (7664-41-7) + nitrogen

Conditions	Yield
at 120 - 130℃;

hydrogenchloride (7647-01-0) + 3-methyl-6-nitro-3H-benzo[d][1,2,3]triazin-4-one → 2-chloro-5-nitrobenzoic acid (2516-96-3) + methylamine (74-89-5) + nitrogen

Conditions	Yield
at 120 - 130℃;

sulfuric acid (7664-93-9) + nitric acid (7697-37-2) + ortho-chlorobenzoic acid (118-91-2) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

nitric acid (7697-37-2) + ortho-chlorobenzoic acid (118-91-2) → 2-chloro-5-nitrobenzoic acid (2516-96-3) + 2-chloro-3-nitrobezoic acid (3970-35-2)

Conditions	Yield
at -30 - 0℃;

5-nitro-2-sulfo-benzoic acid (40567-35-9) + phosphorus pentachloride (10026-13-8, 874483-75-7) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
at 180℃;

6-chloro-3-nitro-toluene-ω-sulfonic acid → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
With permanganate(VII) ion

diazotized 3-amino-5-nitro-benzoic acid → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
With copper(I) chloride

sulfuric acid (7664-93-9) + 4-chloro-3-(trifluoromethyl)nitrobenzene (777-37-7) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

2'-chloro-5'-nitroacetophenone (23082-50-0) + potassium permanganate → 2-chloro-5-nitrobenzoic acid (2516-96-3)

(2-chloro-5-nitro-phenyl)-methanesulfonic acid (749147-27-1) + permanganate → 2-chloro-5-nitrobenzoic acid (2516-96-3)

2-Chlorobenzonitrile (873-32-5) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
Multi-step reaction with 2 steps 1: diluted sulfuric acid 2: nitric acid View Scheme

4-chloro-3-cyanonitrobenzene (16588-02-6) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
Multi-step reaction with 2 steps 1: aq. NaOH solution; aqueous hydrogen peroxide 2: aqueous sulfuric acid; sodium nitrite View Scheme
Multi-step reaction with 2 steps 1: concentrated sulfuric acid 2: concentrated aqueous hydrochloric acid View Scheme

2-Chloroaniline (95-51-2) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
Multi-step reaction with 3 steps 1: hydrochloric acid; sodium nitrite / die Loesung mit Wasserdampf destillieren 2: diluted sulfuric acid 3: nitric acid View Scheme
Multi-step reaction with 3 steps 1: Diazotization.Behandlung der Diazoloesung mit Kaliumkupfercyanuerloesung 2: diluted sulfuric acid 3: nitric acid View Scheme

2-chloro-benzaldehyde (89-98-5) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
Multi-step reaction with 2 steps 1: sulfuric acid; sodium nitrate / 0 - 5 °C 2: permanganate; alkali View Scheme

2-chloro-5-nitrobenzoylchloride (25784-91-2) → 2-chloro-5-nitrobenzoic acid (2516-96-3)

Conditions	Yield
Multi-step reaction with 2 steps 2: aq. NaOH View Scheme

2-chloro-5-nitrobenzaldehyde (6361-21-3) → 2-chloro-5-nitrobenzoic acid (2516-96-3) + 2-chloro-5-nitrobenzyl alcohol (80866-80-4)

Conditions	Yield
With sodium borohydrid In methanol; water
With sodium borohydrid In methanol; water
With sodium borohydrid In methanol; water

2-chloro-5-nitrobenzoic acid (2516-96-3) → 2-chloro-5-nitrobenzoylchloride (25784-91-2)

Conditions	Yield
With thionyl chloride	100%
In toluene	95%
With phosphorus pentachloride In benzene for 3h; Heating;	93.1%

2-chloro-5-nitrobenzoic acid (2516-96-3) + 3-amino-4-hydroxytoluene (95-84-1) → 2-(2-amino-4-methylphenoxy)-5-nitrobenzoic acid (78460-76-1)

Conditions	Yield
With N,N,N,N,N,N-hexamethylphosphoric triamide; sodium hydride 1.)ice-bath cooling, 1.5 h 2.)r.t., overnight;	100%

2-chloro-5-nitrobenzoic acid (2516-96-3) → 4-chlorobenzonitrile (100-00-5)

Conditions	Yield
With silver carbonate In dimethyl sulfoxide; N,N-dimethyl-formamide at 110℃; for 16h; Inert atmosphere;	100%
With silver carbonate In dimethyl sulfoxide at 120℃; for 16h;	90%
With silver(I) acetate; potassium carbonate In 1-methyl-pyrrolidin-2-one at 120℃; for 16h; Inert atmosphere;	85%

2-chloro-5-nitrobenzoic acid (2516-96-3) + cyclohexylamine (108-91-8) → 2-(cyclohexylamino)-5-nitrobenzoic acid (66380-72-1)

Conditions	Yield
at 120℃; for 0.0833333h; microwave irradiation;	99%
Stage #1: 2-chloro-5-nitrobenzoic acid; cyclohexylamine at 120℃; for 0.1h; Microwave heating; Stage #2: With sodium hydroxide In dichloromethane; water Stage #3: With hydrogenchloride In water Acidic aqueous solution;	31%
With water; sodium carbonate at 140℃;

pyrrolidine (123-75-1) + 2-chloro-5-nitrobenzoic acid (2516-96-3) → 2-tetrahydropyrrolyl-5-nitrobenzoic acid (19555-48-7)

Conditions	Yield
at 80℃; for 0.0833333h; microwave irradiation;	99%
With copper; potassium carbonate In N,N-dimethyl-formamide at 25℃; for 0.25h; Ullmann condensation; ultrasonic irradiation;	92%
In ethanol for 7h; Heating;	89%

2-chloro-5-nitrobenzoic acid (2516-96-3) → 2-chloro-5-nitrobenzyl alcohol (80866-80-4)

Conditions	Yield
With sodium tetrahydroborate; boron trifluoride diethyl etherate In tetrahydrofuran at 0 - 20℃; for 1h;	99%
With sodium tetrahydroborate; boron trifluoride diethyl etherate In tetrahydrofuran at 0 - 20℃;	90%
With phenylsilane; C34H30CoO6; potassium In tetrahydrofuran at 20℃; for 20h; Inert atmosphere; Schlenk technique; Glovebox;	71%
With sodium tetrahydroborate; boron trifluoride diethyl etherate In tetrahydrofuran at 0 - 20℃; for 1h;

2-chloro-5-nitrobenzoic acid (2516-96-3) + Cyclopentamine (1003-03-8) → 2-(cyclopentylamino)-5-nitrobenzoic acid (247568-48-5)

Conditions	Yield
at 120℃; for 0.0833333h; microwave irradiation;	99%

2-chloro-5-nitrobenzoic acid (2516-96-3) + di-n-propylamine (142-84-7) → 2-(dipropylamino)-5-nitrobenzoic acid

Conditions	Yield
at 100℃; for 0.0833333h; microwave irradiation;	99%
With copper; potassium carbonate In N,N-dimethyl-formamide at 25℃; for 0.333333h; Ullmann condensation; ultrasonic irradiation;	79%

2-chloro-5-nitrobenzoic acid (2516-96-3) + dibutylamine (111-92-2) → 2-Dibutylamino-5-nitro-benzoic acid (83909-53-9)

Conditions	Yield
for 3h; Heating;	98%

octanol (111-87-5) + 2-chloro-5-nitrobenzoic acid (2516-96-3) → octyl 2-chloro-5-nitrobenzoate (1256568-06-5)

Conditions	Yield
With 25 wtpercent H3PO4/ZrO2-TiO2 at 140℃; for 0.75h; Neat (no solvent); chemoselective reaction;	98%

1-Decanol (112-30-1) + 2-chloro-5-nitrobenzoic acid (2516-96-3) → decyl 2-chloro-5-nitrobenzoate (1256568-05-4)

Conditions	Yield
With 25 wtpercent H3PO4/ZrO2-TiO2 at 160℃; for 0.5h; Neat (no solvent); chemoselective reaction;	98%

methanol (67-56-1) + 2-chloro-5-nitrobenzoic acid (2516-96-3) → 2-chloro-5-nitro-benzoic acid methyl ester (6307-82-0)

Conditions	Yield
sulfuric acid for 24h; Heating / reflux;	97.9%
With sulfuric acid for 24h; Reflux;	96%
With sulfuric acid at 80℃; for 24h;	96%

2-chloro-5-nitrobenzoic acid (2516-96-3) → 2-chloro-5-aminobenzoic acid (89-54-3)

Conditions	Yield
With hydrogen; platinum	97%
With hydrogen; platinum(IV) oxide In ethanol Ambient temperature;	95%
With iron; ammonium chloride In ethanol; water at 78 - 80℃; for 5h;	95.1%

2-chloro-5-nitrobenzoic acid (2516-96-3) → 5-nitrosalicylic acid (96-97-9)

Conditions	Yield
With pyridine; water; potassium carbonate; copper for 0.25h; sonication;	97%
With water; potassium hydroxide for 6h; Heating; Large scale;	97%
Stage #1: 2-chloro-5-nitrobenzoic acid With potassium hydroxide In water at 25 - 30℃; under 1875.19 Torr; for 0.333333h; Industrial scale; Stage #2: In water at 125 - 130℃; for 5h; Industrial scale;	96%

2-chloro-5-nitrobenzoic acid (2516-96-3) + glycine (56-40-6) → 2-[(carboxymethyl)amino]-5-nitrobenzoic acid (26491-02-1)

Conditions	Yield
With copper; potassium carbonate In N,N-dimethyl-formamide at 25℃; for 0.416667h; Ullmann condensation; ultrasonic irradiation;	97%
With copper; potassium carbonate In N,N-dimethyl-formamide for 2h; Heating;	97%
With copper; sodium carbonate In water for 2h; Reflux;	50%
With water; copper; sodium carbonate

2-chloro-5-nitrobenzoic acid (2516-96-3) + 3-(2-hydroxyethyl)-1-methyl-1H-imidazol-3-ium tetrafluoroborate → BF4(1-)*C13H13ClN3O4(1+)

Conditions	Yield
With dmap; dicyclohexyl-carbodiimide In dichloromethane at 20℃; for 12h;	97%

n-heptan1ol (111-70-6) + 2-chloro-5-nitrobenzoic acid (2516-96-3) → heptyl 2-chloro-5-nitrobenzoate (1256568-07-6)

Conditions	Yield
With 25 wtpercent H3PO4/ZrO2-TiO2 at 130℃; for 0.75h; Neat (no solvent); chemoselective reaction;	97%

N-methylcyclohexylamine (626-67-5) + 2-chloro-5-nitrobenzoic acid (2516-96-3) → (2-chloro-5-nitrophenyl)(piperidin-1-yl)methanone

Conditions	Yield
Stage #1: N-methylcyclohexylamine With iodine; triphenylphosphine In dichloromethane at 0℃; for 0.166667h; Stage #2: 2-chloro-5-nitrobenzoic acid In dichloromethane at 25℃;	96%

2-chloro-5-nitrobenzoic acid (2516-96-3) + triethylamine (121-44-8) → 2-chloro-5-nitro-N,N-diethylbenzamide (67272-98-4)

Conditions	Yield
Stage #1: triethylamine With iodine; triphenylphosphine In dichloromethane at 0℃; for 0.166667h; Stage #2: 2-chloro-5-nitrobenzoic acid In dichloromethane at 25℃; Reagent/catalyst;	95%
With iodine; triphenylphosphine In dichloromethane at 0 - 20℃;	75%

disulfiram (97-77-8) + 2-chloro-5-nitrobenzoic acid (2516-96-3) → 2-chloro-5-nitro-N,N-diethylbenzamide (67272-98-4)

Conditions	Yield
With di-tert-butyl peroxide; copper(I) bromide In ethyl acetate at 120℃;	95%

2-chloro-5-nitrobenzoic acid (2516-96-3) + ethanolamine (141-43-5) + acetone (67-64-1) → N-(1,1-dimethyl-3-oxobutyl)monoethanolammonium 2-chloro-5-nitrobenzoate

Conditions	Yield
at 20℃;	95%

2-chloro-5-nitrobenzoic acid (2516-96-3) + p-toluidine (106-49-0) → 2-chloro-5-nitro-N-(p-tolyl)benzamide (292638-37-0)

Conditions	Yield
With EDC-polymer In tetrahydrofuran at 20℃; for 4h;	94%

2-chloro-5-nitrobenzoic acid (2516-96-3) + tribenzylamine (620-40-6) → C21H17ClN2O3

Conditions	Yield
Stage #1: tribenzylamine With iodine; triphenylphosphine In dichloromethane at 0℃; for 0.166667h; Stage #2: 2-chloro-5-nitrobenzoic acid In dichloromethane at 25℃;	94%

2-chloro-5-nitrobenzoic acid (2516-96-3) + N,O-dimethylhydroxylamine*hydrochloride (6638-79-5) → 2-chloro-N-methoxy-N-methyl-5-nitrobenzamide

Conditions	Yield
Stage #1: 2-chloro-5-nitrobenzoic acid With N-Bromosuccinimide; triphenylphosphine In dichloromethane at 0℃; for 0.25h; Stage #2: N,O-dimethylhydroxylamine*hydrochloride With triethylamine In dichloromethane at 20℃; for 1h; chemoselective reaction;	94%

2-chloro-5-nitrobenzoic acid (2516-96-3) + aniline (62-53-3) → NPB (16927-50-7)

Conditions	Yield
With copper diacetate; potassium carbonate at 185℃; for 2h; Ullmann Condensation; Inert atmosphere;	93%
With potassium carbonate In water at 150℃; for 2h; Temperature; Time;	90%
With sodium carbonate In N,N-dimethyl-formamide for 4h; Ullmann Condensation; Reflux;	90%

azonane (5661-71-2) + 2-chloro-5-nitrobenzoic acid (2516-96-3) → 5-nitro-2-octamethyleneimino-benzoic acid (78243-43-3)

Conditions	Yield
With sodium carbonate In ethanol for 4h; Heating;	93%

2-chloro-5-nitrobenzoic acid (2516-96-3) + hexan-1-ol (111-27-3) → hexyl 2-chloro-5-nitrobenzoate (1256568-09-8)

Conditions	Yield
With 25 wtpercent H3PO4/ZrO2-TiO2 at 120℃; for 1.66667h; Neat (no solvent); chemoselective reaction;	93%

2-chloro-5-nitrobenzoic acid (2516-96-3) → potassium 2-chloro-5-nitrobenzoate

Conditions	Yield
With potassium tert-butylate In ethanol at 20℃; for 1h; Inert atmosphere;	93%
With potassium tert-butylate In ethanol at 20℃;

Upstream product

• 16588-15-1 2-chloro-5-nitro-benzamide 
• 96-97-9 5-nitrosalicylic acid 
• 6361-21-3 2-chloro-5-nitrobenzaldehyde 
• 7647-01-0 hydrogenchloride 
• 91532-29-5 6-nitrobenzo[d][1,2,3]triazin-4(3H)-one 
• 7664-93-9 sulfuric acid 
• 7697-37-2 nitric acid 
• 118-91-2 ortho-chlorobenzoic acid 
• 40567-35-9 5-nitro-2-sulfo-benzoic acid 
• 10026-13-8 phosphorus pentachloride 
• 89-98-5 2-chloro-benzaldehyde 
• 831-50-5 1-chloro-4-nitro-2-(trichloromethyl)benzene 
• 25784-91-2 2-chloro-5-nitrobenzoylchloride 
• 95-51-2 o-chloroaniline 

Downstream Products

• 108621-76-7 2-(2-ethyl-phenoxy)-5-nitro-benzoic acid 
• 807293-00-1 2-(2-acetylamino-thiazol-5-ylmercapto)-5-nitro-benzoic acid 
• 109254-64-0 5,5'-dinitro-2,2'-m-phenylenedimercapto-di-benzoic acid 
• 62086-52-6 2-(naphthalen-1-ylamino)-5-nitrobenzoic acid 
• 393570-60-0 2-(3-amino-phenylamino)-5-nitrobenzoic acid 
• 61767-78-0 2-(4-chlorophenylamino)-5-nitrobenzoic acid 
• 6686-68-6 2-[(4-methoxyphenyl)amino]-5-nitrobenzoic acid 
• 26759-50-2 2-carboxymethylsulfanyl-5-nitro-benzoic acid 
• 6345-67-1 2-carboxy-4-nitrodiphenyl sulphide 
• 70132-87-5 2-chloro-4'-methoxy-5-nitro-benzophenone 
• 730978-51-5 N-(4-nitrophenyl)-5-nitroanthranilic acid 
• 78160-05-1 5-nitro-2-p-tolylsulfanyl-benzoic acid 
• 90656-49-8 2-(3-chlorophenylamino)-5-nitrobenzoic acid 
• 66949-29-9 2-(4-chloro-phenylsulfanyl)-5-nitro-benzoic acid 

Relevant articles and documents

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The invention discloses a preparation method for 2-chloro-5-iodobenzoic acid. The preparation method is characterized in that cheap o-chlorobenzoic acid is taken as a starting material to obtain 2-chloro-5-iodobenzoic acid through nitration, reduction and diazotization iodination. The method shortens reaction steps, increases the yield and is suitable for industrial production.

Preparation method of 2-chloride-5-nitrobenzoic acid

The invention provides a preparation method of 2-chloride-5-nitrobenzoic acid. The preparation method comprises the following steps: mixing concentrated nitric acid and fuming sulphuric acid with the SO3 concentration of 20 percent according to the mass ratio of 1:(2-3), and controlling the temperature of the solution to be less than 10 DEG C in a mixing process; dripping 2-chloride trichlorotoluene, controlling the temperature of reaction liquid to be 0 to 10 DEG C, and continuously stirring at the end of dripping till the reaction is completed; pouring the reaction liquid into ice water, extracting with dichloromethane, washing an organic phase with a saturated sodium bicarbonate solution, and concentrating and drying to obtain 2-chloride-5-nitro trichlorotoluene; preparing concentrated sulfuric acid with the concentration of 85 weight percent, heating to 60 to 65 DEG C, adding the 2-chloride-5-nitro trichlorotoluene in batches, and preserving the heat till the reaction is completed; cooling the reaction liquid, adding water into the reaction liquid for dilution, extracting with ethyl acetate, taking an organic phase, and performing washing and concentration to obtain 2-chloride-5-nitrobenzoic acid. The technological steps are more reasonable in design and high in operability; the number of byproducts is small; the prepared product is relatively high in purity and can meet the requirement on industrial application.