603-81-6

Basic information

• Product Name: 2,3-Diaminobenzoic acid
• Synonyms: 3-carboxy-1,2-diaminobenzene;2,3-DIAMINOBENZOIC ACID;2,3-Diaminobenzonicacid;2,3-bis(azanyl)benzoic acid;2,3-diaMinobenzoic acid hydrochloride
• CAS NO: 603-81-6
• Molecular Formula: C₇H₈N₂O₂
• Molecular Weight: 152.15
• Product Categories: Aromatic Carboxylic Acids, Amides, Anilides, Anhydrides & Salts;pharmacetical;Carboxylic Acids;Phenyls & Phenyl-Het;Benzoic acid;API intermediates;Carboxylic Acids;Phenyls & Phenyl-Het
• Mol File: 603-81-6.mol
• Article Data: 15

Chemical Properties

• Melting Point: 198-204 °C
• Boiling Point: 274.61°C (rough estimate)
• Flash Point: 185.3 °C
• Appearance: /
• Density: 1.2804 (rough estimate)
• Vapor Pressure: 1.53E-06mmHg at 25°C
• Refractive Index: 1.5200 (estimate)
• Storage Temp.: Keep in dark place,Inert atmosphere,Room temperature
• PKA: 5.10±0.10(Predicted)
• CAS DataBase Reference: 2,3-Diaminobenzoic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 2,3-Diaminobenzoic acid(603-81-6)
• EPA Substance Registry System: 2,3-Diaminobenzoic acid(603-81-6)

Safety Data

• Hazard Codes: Xi,Xn
• Statements: 22-36
• Safety Statements: 26
• HazardClass: IRRITANT
• Hazardous Substances Data: 603-81-6(Hazardous Substances Data)

Usage

General Description

2,3-Diaminobenzoic acid is an organic compound with the chemical formula C7H8N2O4. It is a derivative of benzoic acid, with two amino groups attached at the 2 and 3 positions. It is primarily used as a building block in the synthesis of various pharmaceuticals, dyes, and polymers. 2,3-Diaminobenzoic acid is also known for its potential role in the treatment of certain neurological conditions, such as Parkinson's disease. Its chemical properties and structure make it valuable for a wide range of applications, from organic synthesis to medicinal chemistry.

InChI:InChI=1/C7H8N2O2/c8-5-3-1-2-4(6(5)9)7(10)11/h1-3H,8-9H2,(H,10,11)

Synthetic route

3-nitroanthranilic acid (606-18-8) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
With sodium dithionite In ethanol for 1h; Heating;	74%
With palladium 10% on activated carbon; hydrogen In methanol under 760.051 Torr;	69%
With hydrogen; 10percent Pd/C In methanol under 760.051 Torr;	66%

3-Amino-2-nitrobenzoic acid (116465-92-0) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
With hydrogenchloride; tin(ll) chloride
With hydrogenchloride; tin

2-acetylamino-3-nitro-benzoic acid (90417-80-4) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
With hydrogenchloride; zinc

hydrogenchloride (7647-01-0) + 3-Amino-2-nitrobenzoic acid (116465-92-0) + tin → 2,3-diaminobenzoic acid (603-81-6)

2-carbamoyl-3-nitrobenzoic acid (77326-45-5) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: aq. KOH; Br2 / 80 °C 2: NaOH; hydrazine hydrate; Raney Ni View Scheme
Multi-step reaction with 2 steps 1: 93 percent / Br2; aq. KOH / 3 h / 60 °C 2: 66 percent / H2 / 10percent Pd/C / methanol / 760.05 Torr View Scheme
Multi-step reaction with 2 steps 1: NaOCl, aq. NaOH 2: H2, aq. NaOH / Pd/C / 4 h / 760 Torr View Scheme
Multi-step reaction with 2 steps 1: sodium hypochlorite; water; sodium hydroxide / 0 - 80 °C 2: hydrazine hydrate; sodium hydroxide / methanol / Reflux View Scheme
Multi-step reaction with 2 steps 1: bromine; potassium hydroxide / water / 0 - 60 °C 2: hydrogen; palladium 10% on activated carbon / methanol / 760.05 Torr View Scheme

2-Amino-3-nitrobenzoic acid,ethyl ester (61063-11-4) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: aq. KOH / Heating 2: H2, aq. NaOH / Pd/C View Scheme

ethyl 2-carboxy-3-nitrobenzoate (16533-45-2) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 5 steps 1: SOCl2 / 1 h / Heating 2: aq. NaN3 / acetone / 1 h / below 25 deg C 3: aq. AcOH / 0.17 h / Heating 4: aq. KOH / Heating 5: H2, aq. NaOH / Pd/C View Scheme

3-nitro-phthalic acid-1-ethyl ester-2-chloride (136285-66-0) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 4 steps 1: aq. NaN3 / acetone / 1 h / below 25 deg C 2: aq. AcOH / 0.17 h / Heating 3: aq. KOH / Heating 4: H2, aq. NaOH / Pd/C View Scheme

2-Azidocarbonyl-3-nitro-benzoic acid ethyl ester (124341-05-5) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 3 steps 1: aq. AcOH / 0.17 h / Heating 2: aq. KOH / Heating 3: H2, aq. NaOH / Pd/C View Scheme

2-nitro-3-(N'-nitro-ureido)-benzoic acid (100949-43-7) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: water 2: tin; hydrochloric acid View Scheme

2-methyl-1H-indole (95-20-5) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 3 steps 1: diethyl ether 2: potassium permanganate; aqueous KOH-solution 3: zinc; aqueous hydrochloric acid View Scheme

2-methyl-3-oximino-3H-indole (3484-07-9) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 3 steps 1: diethyl ether 2: potassium permanganate; aqueous KOH-solution 3: zinc; aqueous hydrochloric acid View Scheme

2-methyl-7-nitro-indol-3-one oxime → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: potassium permanganate; aqueous KOH-solution 2: zinc; aqueous hydrochloric acid View Scheme

2,3-di-nitrobenzoic acid (15147-64-5) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
With stannous chloride In hydrogenchloride; water; acetic acid

3-nitrophthalic acid anhydride (641-70-3) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 3 steps 1: ammonia; water / 0 °C 2: sodium hypochlorite; water; sodium hydroxide / 0 - 80 °C 3: hydrazine hydrate; sodium hydroxide / methanol / Reflux View Scheme
Multi-step reaction with 3 steps 1: ammonia 2: bromine; sodium hydroxide 3: sodium hydroxide / raney Nickel / methanol View Scheme
Multi-step reaction with 3 steps 1: ammonium hydroxide / water / 0 °C 2: bromine; potassium hydroxide / water / 0 - 60 °C 3: hydrogen; palladium 10% on activated carbon / methanol / 760.05 Torr View Scheme
Multi-step reaction with 3 steps 2: sodium hydroxide; sodium hypochlorite / water 3: palladium-carbon / methanol View Scheme

3-nitrophthalic acid (603-11-2) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 4 steps 1: acetic anhydride / Reflux 2: ammonia; water / 0 °C 3: sodium hypochlorite; water; sodium hydroxide / 0 - 80 °C 4: hydrazine hydrate; sodium hydroxide / methanol / Reflux View Scheme

2-aminoacetyl-3-nitrobenzoic acid (1234834-07-1) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: bromine; sodium hydroxide 2: sodium hydroxide / raney Nickel / methanol View Scheme

ammonium 3-nitrophthalamidate (316833-29-1) → 2,3-diaminobenzoic acid (603-81-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: sodium hydroxide; sodium hypochlorite / water 2: palladium-carbon / methanol View Scheme

furil (492-94-4) + 2,3-diaminobenzoic acid (603-81-6) → 2,3-bis-(2-furyl)-5-quinoxalinecarboxylic acid (90833-34-4)

Conditions	Yield
In hydrogenchloride for 1h; heating on boiling water bath;	99.8%

orthoformic acid triethyl ester (122-51-0) + 2,3-diaminobenzoic acid (603-81-6) → benzimidazole-4-carboxylic acid (46006-36-4)

Conditions	Yield
at 130℃;	98%
at 130℃;	7.3 g

2,3-diaminobenzoic acid (603-81-6) → 2,1,3-benzoselenadiazole-4-carboxylic acid (27206-21-9)

Conditions	Yield
With hydrogenchloride; selenium(IV) oxide In water at 80℃; for 2h;	97%

Difluoroacetic acid (381-73-7) + 2,3-diaminobenzoic acid (603-81-6) → 2-(difluoromethyl)-1H-benzimidazole-4-carboxylic acid (1246548-14-0)

Conditions	Yield
Stage #1: Difluoroacetic acid; 2,3-diaminobenzoic acid With hydrogenchloride In water for 16h; Reflux; Stage #2: With ammonia In water	96%
With hydrogenchloride In water at 20℃; for 16h; Reflux;	96%

indan-1,2,3-trione hydrate (485-47-2) + 2,3-diaminobenzoic acid (603-81-6) → 11-oxo-11H-indeno<1,2-b>quinoxaline-6-carboxylic acid (154458-02-3)

Conditions	Yield
In ethanol for 2h; Reflux;	96%

6-chloronicotinylaldehyde (23100-12-1) + 2,3-diaminobenzoic acid (603-81-6) → 2-(6-chloropyridin-3-yl)-1H-benzo[d]imidazole-4-carboxylic acid (330948-01-1)

Conditions	Yield
With sodium disulfite In N,N-dimethyl-formamide at 100℃; for 18h;	95%

dimethylglyoxal (431-03-8) + 2,3-diaminobenzoic acid (603-81-6) → 2,3-dimethyl-5-quinoxalinecarboxylic acid (6924-67-0)

Conditions	Yield
In acetic acid for 2h; Heating;	94%

1,2-bis(4-methoxyphenyl)-1,2-ethanedione (1226-42-2) + 2,3-diaminobenzoic acid (603-81-6) → 2,3-bis-(4-methoxyphenyl)-5-quinoxalinecarboxylic acid (90833-30-0)

Conditions	Yield
In hydrogenchloride for 1h; heating on boiling water bath;	91.9%
With acetic acid for 3h; Reflux;	26%

benzil (134-81-6) + 2,3-diaminobenzoic acid (603-81-6) → 2,3-diphenyl-5-quinoxalinecarboxylic acid (90833-20-8)

Conditions	Yield
In acetic acid for 2h; Heating;	89.4%

orthoformic acid triethyl ester (122-51-0) + 2,3-diaminobenzoic acid (603-81-6) → 2-ethoxyl-1H-benzimidazole-4-carboxylic acid (1234834-29-7)

Conditions	Yield
In water; acetic acid	89%

5-nitrofurane-2-carboxaldehyde (698-63-5) + 2,3-diaminobenzoic acid (603-81-6) → 2-(5-nitrofuran-2-yl)-1H-benzo[d]imidazole-5-carboxylic acid

Conditions	Yield
With oxygen; potassium hexacyanoferrate (III) In methanol; water for 16h; Reflux;	88%

pyridine-2-carbaldehyde (1121-60-4) + 2,3-diaminobenzoic acid (603-81-6) → 2-(pyridin-2-yl)-1H-benzo[d]imidazole-4-carboxylic acid (124340-85-8)

Conditions	Yield
In N,N-dimethyl-formamide at 80℃; for 120h;	85%
With potassium hexacyanoferrate(III) In N,N-dimethyl-formamide at 60℃; for 10h;	78%
With copper diacetate; acetic acid In methanol; water Heating;
With potassium hexacyanoferrate(III) In methanol Heating;
With p-benzoquinone In 1,4-dioxane at 80℃;

2,3-diaminobenzoic acid (603-81-6) + 2,3,4-trimethoxybenzaldehyde (2103-57-3) → 2-(2,3,4-trimethoxyphenyl)-1H-benzimidazole-4-carboxylic acid (124341-04-4)

Conditions	Yield
In N,N-dimethyl-formamide at 80℃; for 120h;	85%
With copper diacetate; acetic acid In methanol; water Heating;

tert-butyl 3-(2-formylphenoxy)pyrrolidine-1-carboxylate (1203486-46-7) + 2,3-diaminobenzoic acid (603-81-6) → 2-(2-(1-(tert-butoxycarbonyl)pyrrolidin-3-yloxy)phenyl)-1H-benzo[d]imidazole-4-carboxylic acid (1203486-47-8)

Conditions	Yield
With sodium disulfite In N,N-dimethyl-formamide at 90℃; for 18h;	84%

pyridine-4-carbaldehyde (872-85-5) + 2,3-diaminobenzoic acid (603-81-6) → 2-(pyridin-4-yl)-1H-benzimidazole-4-carboxylic acid (124340-93-8)

Conditions	Yield
In N,N-dimethyl-formamide at 80℃; for 120h;	83%
With potassium hexacyanoferrate(III) In N,N-dimethyl-formamide at 60℃; for 10h;	81%
With copper diacetate; acetic acid In methanol; water Heating;

3-pyridinecarboxaldehyde (500-22-1) + 2,3-diaminobenzoic acid (603-81-6) → 2-(pyridin-3-yl)-1H-benzimidazole-4-carboxylic acid (124340-89-2)

Conditions	Yield
In N,N-dimethyl-formamide at 80℃; for 120h;	83%
With potassium hexacyanoferrate(III) In N,N-dimethyl-formamide at 60℃; for 10h;	80%
With copper diacetate; acetic acid In methanol; water Heating;
With potassium hexacyanoferrate(III) In methanol Heating;
With p-benzoquinone In 1,4-dioxane at 80℃;

cycloheptane-1,2-dione (3008-39-7) + 2,3-diaminobenzoic acid (603-81-6) → 7,8,9,10-Tetrahydro-6H-cyclohepta[b]quinoxaline-1-carboxylic acid (90833-19-5)

Conditions	Yield
In acetic acid for 2h; Heating;	82.4%

5-nitrofurane-2-carboxaldehyde (698-63-5) + 2,3-diaminobenzoic acid (603-81-6) → 2-(5-nitrofuran-2-yl)-1H-benzimidazole-4-carboxylic acid (1160269-54-4)

Conditions	Yield
In N,N-dimethyl-formamide at 80℃; for 120h;	82%

3,4-dimethoxy-benzaldehyde (120-14-9) + 2,3-diaminobenzoic acid (603-81-6) → 2-(3,4-dimethoxyphenyl)-1H-benzimidazole-4-carboxylic acid (313278-99-8)

Conditions	Yield
In N,N-dimethyl-formamide at 80℃; for 120h;	81%
With copper diacetate In methanol; water Heating;	46%

1-ferrocenyl-2-phenylethane-1,2-dione + 2,3-diaminobenzoic acid (603-81-6) → ferrocenylphenylquinoxalylcarboxylic acid

Conditions	Yield
In chlorobenzene N2-atmosphere; 140°C (1 h); CH2Cl2 addn., filtering, washing (H2O), drying (Na2SO4), concg., chromy.(SiO2, Et2O), isolated as mixture of regioisomers; elem. anal.;	81%

furfural (98-01-1) + 2,3-diaminobenzoic acid (603-81-6) → 2-(furan-2-yl)-1H-benzimidazole-4-carboxylic acid (124340-76-7)

Conditions	Yield
In N,N-dimethyl-formamide at 80℃; for 120h;	80%
With copper diacetate; acetic acid In methanol; water Heating;

acetylacetone (123-54-6) + trifluoroacetic acid (76-05-1) + 2,3-diaminobenzoic acid (603-81-6) → 6-carboxy-2,4-dimethyl-3H-benzo[b][1,4]diazepin-1-ium trifluoroacetate

Conditions	Yield
In ethanol at 20℃; for 0.5h;	80%

acetylacetone (123-54-6) + 2,3-diaminobenzoic acid (603-81-6) → 6-carboxy-2,4-dimethyl-3H-benzo[b][1,4]diazepin-1-ium hydrogensulfonate

Conditions	Yield
With hydrogenchloride; sulfuric acid In ethanol at 20℃; for 0.5h;	80%

sodium 1-hydroxy-2-methyl-1-propanesulfonate (13023-74-0) + 2,3-diaminobenzoic acid (603-81-6) → 2-(propan-2-yl)-1H-benzimidazole-4-carboxylic acid

Conditions	Yield
With sodium hydroxide In water at 15 - 25℃; for 13h; Green chemistry;	79%

4-hydroxy-benzaldehyde (123-08-0) + 2,3-diaminobenzoic acid (603-81-6) → 2-(4-hydroxyphenyl)-1H-benzimidazole-4-carboxylic acid

Conditions	Yield
With potassium hexacyanoferrate(III) In N,N-dimethyl-formamide at 60℃; for 10h;	78%
With copper diacetate In methanol; water Heating;

formic acid (64-18-6) + 2,3-diaminobenzoic acid (603-81-6) → benzimidazole-4-carboxylic acid (46006-36-4)

Conditions	Yield
With hydrogenchloride for 1h; Heating;	77%
With hydrogenchloride In water for 2h; Reflux;	51%

2,3-diaminobenzoic acid (603-81-6) → benzo[d]oxazole-4-carboxylic acid (208772-23-0) + benzimidazole-4-carboxylic acid (46006-36-4)

Conditions	Yield
With formic acid In hydrogenchloride; methanol	A n/a B 77%

2-Trifluoromethylbenzaldehyde (447-61-0) + 2,3-diaminobenzoic acid (603-81-6) → 2-(2-(trifluoromethyl)phenyl)-1H-benzo[d]imidazole-4-carboxylic acid (1203486-37-6)

Conditions	Yield
With sodium disulfite In N,N-dimethyl-formamide at 100℃; for 17h;	74%

salicylaldehyde (90-02-8) + 2,3-diaminobenzoic acid (603-81-6) → 2-(2-hydroxyphenyl)-1H-benzo[d]imidazole-4-carboxylic acid

Conditions	Yield
In N,N-dimethyl-formamide at 80℃;	73%
With sodium metabisulfite In N,N-dimethyl acetamide Heating;	25.2%

Upstream product

• 116465-92-0 3-Amino-2-nitrobenzoic acid 
• 606-18-8 3-nitroanthranilic acid 
• 7647-01-0 hydrogenchloride 
• 95-20-5 2-methyl-1H-indole 
• 316833-29-1 ammonium 3-nitrophthalamidate 
• 1234834-07-1 2-aminoacetyl-3-nitrobenzoic acid 
• 603-11-2 3-nitrophthalic acid 
• 641-70-3 3-nitrophthalic acid anhydride 
• 15147-64-5 2,3-di-nitrobenzoic acid 
• 3484-07-9 2-methyl-3-oximino-3H-indole 
• 100949-43-7 2-nitro-3-(N'-nitro-ureido)-benzoic acid 
• 124341-05-5 2-Azidocarbonyl-3-nitro-benzoic acid ethyl ester 
• 136285-66-0 3-nitro-phthalic acid-1-ethyl ester-2-chloride 
• 16533-45-2 ethyl 2-carboxy-3-nitrobenzoate 

Downstream Products

• 291289-41-3 2-oxo-2,3-dihydro-1H-benzimidazole-4-carboxylic acid 
• 46006-36-4 benzimidazole-4-carboxylic acid 
• 95-54-5 1,2-diamino-benzene 
• 15719-64-9 methylammonium carbonate 
• 124340-85-8 2-(pyridin-2-yl)-1H-benzo[d]imidazole-4-carboxylic acid 
• 124340-93-8 2-(pyridyl-4-yl)-1H-benzimidazole-4-carboxylic acid 
• 124340-88-1 2-(3-Chloro-phenyl)-1H-benzoimidazole-4-carboxylic acid 
• 90833-24-2 2,3-bis-(4-chlorophenyl)-5-quinoxalinecarboxylic acid 
• 90833-30-0 2,3-bis-(4-methoxyphenyl)-5-quinoxalinecarboxylic acid 
• 124340-82-5 2-o-Tolyl-1H-benzoimidazole-4-carboxylic acid 
• 124340-83-6 2-(2-methoxyphenyl)-1H-benzimidazole-4-carboxylic acid 
• 90833-20-8 2,3-diphenyl-5-quinoxalinecarboxylic acid 
• 313279-00-4 2-(3,4,5-trimethoxyphenyl)-1H-benzimidazole-4-carboxylic acid 
• 313278-99-8 2-(3,4-dimethoxyphenyl)-1H-benzimidazole-4-carboxylic acid 

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