43115-40-8

Basic information

• Product Name: 2-AMINO-4-(ETHYLSULFONYL)PHENOL
• Synonyms: 2-AMINO-4-(ETHYLSULFONYL)PHENOL;2-amino-4-(ethylsulphonyl)phenol;Einecs 256-100-1;4-Ethylsulfonyl-2-aMinophenol;Phenol,2-aMino-4-(ethylsulfonyl)-
• CAS NO: 43115-40-8
• Molecular Formula: C₈H₁₁NO₃S
• Molecular Weight: 201.24
• EINECS: 256-100-1
• Product Categories: Organic Building Blocks;Sulfones;Sulfur Compounds
• Mol File: 43115-40-8.mol
• Article Data: 2

Chemical Properties

• Melting Point: 128-131 °C(lit.)
• Boiling Point: 436.4 °C at 760 mmHg
• Flash Point: 217.7 °C
• Appearance: /
• Density: 1.355 g/cm³
• Vapor Pressure: 3.17E-08mmHg at 25°C
• Refractive Index: 1.588
• Storage Temp.: 2-8°C
• PKA: 7.29±0.20(Predicted)
• CAS DataBase Reference: 2-AMINO-4-(ETHYLSULFONYL)PHENOL(CAS DataBase Reference)
• NIST Chemistry Reference: 2-AMINO-4-(ETHYLSULFONYL)PHENOL(43115-40-8)
• EPA Substance Registry System: 2-AMINO-4-(ETHYLSULFONYL)PHENOL(43115-40-8)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-37/39
• WGK Germany: 3
• HazardClass: IRRITANT
• Hazardous Substances Data: 43115-40-8(Hazardous Substances Data)

Usage

General Description

2-Amino-4-(ethylsulfonyl)phenol is a chemical compound primarily known for its role in the production of pharmaceuticals and dyes. Its systematic name is 4-(Ethylsulfonyl)-2-aminophenol, and it appears as an off-white to brown crystalline powder. 2-AMINO-4-(ETHYLSULFONYL)PHENOL falls under the class of organosulfur compounds, specifically under sulfones, which are compounds containing a sulfonyl group attached to two carbon atoms. It has a molecular formula of C9H11NO3S. The compound exhibits antioxidant properties and can be used in the manufacture of various phenol derivatives. Its sulfone group may play a significant role in reaction activities due to its stable, inert nature.

InChI:InChI=1/C8H11NO3S/c1-2-13(11,12)6-3-4-8(10)7(9)5-6/h3-5,10H,2,9H2,1H3

Synthetic route

4-(ethylsulfonyl)-2-nitro-phenol (84996-11-2) → 2-amino-4-(ethylsulfonyl)phenol (43115-40-8)

Conditions	Yield
With 5%-palladium/activated carbon; hydrogen In ethanol at 60 - 70℃; under 15001.5 Torr; Temperature; Solvent; Autoclave;	86%
With palladium 10% on activated carbon; hydrogen In isopropyl alcohol at 50℃; under 2280.15 Torr; for 24h;	73%

4-chlorophenyl ethyl sulfide (5120-72-9) → 2-amino-4-(ethylsulfonyl)phenol (43115-40-8)

Conditions	Yield
Multi-step reaction with 4 steps 1: dihydrogen peroxide; sodium tungstate (VI) dihydrate / ethyl acetate / 5 h / 30 - 55 °C / Large scale 2: nitric acid; sulfuric acid / 2 h / 0 - 20 °C / Large scale 3: sodium hydroxide / 3 h / 95 °C / Autoclave 4: hydrogen; palladium 10% on activated carbon / isopropyl alcohol / 24 h / 50 °C / 2280.15 Torr View Scheme

1-(ethylsulfonyl)-4-chlorobenzene (7205-80-3) → 2-amino-4-(ethylsulfonyl)phenol (43115-40-8)

Conditions	Yield
Multi-step reaction with 3 steps 1: nitric acid; sulfuric acid / 2 h / 0 - 20 °C / Large scale 2: sodium hydroxide / 3 h / 95 °C / Autoclave 3: hydrogen; palladium 10% on activated carbon / isopropyl alcohol / 24 h / 50 °C / 2280.15 Torr View Scheme

4-methoxy-phenyl-sulphonyl chloride (98-68-0) → 2-amino-4-(ethylsulfonyl)phenol (43115-40-8)

Conditions	Yield
Multi-step reaction with 5 steps 1: sodium sulfite / water; tetrahydrofuran / 20 h / -5 - 0 °C 2: ethanol / 2 h / 80 °C 3: nitric acid / 70 °C 4: hydrogen bromide; formic acid / 30 h / 90 °C 5: hydrogen; 5%-palladium/activated carbon / ethanol / 60 - 70 °C / 15001.5 Torr / Autoclave View Scheme
Multi-step reaction with 5 steps 1: sodium sulfite / water; tetrahydrofuran / 20 h / -5 - 0 °C 2: methanol / 2 h / 65 °C 3: nitric acid / 70 °C 4: hydrogen bromide; formic acid / 30 h / 90 °C 5: hydrogen; 5%-palladium/activated carbon / ethanol / 60 - 70 °C / 15001.5 Torr / Autoclave View Scheme

sodium 4-methoxybenzenesulfinate (6462-50-6) → 2-amino-4-(ethylsulfonyl)phenol (43115-40-8)

Conditions	Yield
Multi-step reaction with 4 steps 1: ethanol / 2 h / 80 °C 2: nitric acid / 70 °C 3: hydrogen bromide; formic acid / 30 h / 90 °C 4: hydrogen; 5%-palladium/activated carbon / ethanol / 60 - 70 °C / 15001.5 Torr / Autoclave View Scheme
Multi-step reaction with 4 steps 1: methanol / 2 h / 65 °C 2: nitric acid / 70 °C 3: hydrogen bromide; formic acid / 30 h / 90 °C 4: hydrogen; 5%-palladium/activated carbon / ethanol / 60 - 70 °C / 15001.5 Torr / Autoclave View Scheme

1-(ethylsulfonyl)-4-methoxybenzene (7205-79-0) → 2-amino-4-(ethylsulfonyl)phenol (43115-40-8)

Conditions	Yield
Multi-step reaction with 3 steps 1: nitric acid / 70 °C 2: hydrogen bromide; formic acid / 30 h / 90 °C 3: hydrogen; 5%-palladium/activated carbon / ethanol / 60 - 70 °C / 15001.5 Torr / Autoclave View Scheme

4-(ethylsulfonyl)-1-methoxy-2-nitrobenzene (51572-44-2) → 2-amino-4-(ethylsulfonyl)phenol (43115-40-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: hydrogen bromide; formic acid / 30 h / 90 °C 2: hydrogen; 5%-palladium/activated carbon / ethanol / 60 - 70 °C / 15001.5 Torr / Autoclave View Scheme

2-(trifluoromethyl)phenol (444-30-4) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 2-(5-(ethylsulfonyl)benzo[d]oxazol-2-yl)phenol (1193007-08-7)

Conditions	Yield
With sodium hydroxide In water at 80℃; for 2h;	94%

benzofuran-5-carbonyl chloride (56540-70-6) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 2-(benzofuran-5-yl)-5-(ethylsulfonyl)benzo[d]oxazole

Conditions	Yield
In 1,4-dioxane at 210℃; for 0.25h; Microwave irradiation;	85%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + 2-naphthaloyl chloride (2243-83-6) → dibenzoate5-(ethylsulfone)-2-(naphthalen-2-yl)benzo[d]oxazole (945531-77-1)

Conditions	Yield
Stage #1: 2-amino-4-(ethylsulfonyl)phenol; 2-naphthaloyl chloride With sodium hydroxide In water; xylenes at 100 - 155℃; for 2.66667h; Heating / reflux; Stage #2: With methanesulfonic acid In water; xylenes for 0.75h; Heating / reflux;	80%
Stage #1: 2-amino-4-(ethylsulfonyl)phenol; 2-naphthaloyl chloride With sodium hydroxide In water; xylenes at 0 - 155℃; for 2.66667h; Stage #2: With methanesulfonic acid In water; xylenes for 0.75h; Heating / reflux;	80%
In 1,4-dioxane at 210℃; for 0.25h; Microwave irradiation;	75%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + Cinnamoyl chloride (102-92-1) → (E)-5-(ethylsulfonyl)-2-styrylbenzo[d]oxazole (1118624-42-2)

Conditions	Yield
In 1,4-dioxane at 210℃; for 0.25h; Microwave irradiation;	77%

1-[trans-4-(ethyloxy)-1-methylcyclohexyl]-4-piperidinone (950772-15-3) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 2-({1-[trans-4-(ethyloxy)-1-methylcyclohexyl]-4-piperidinyl}amino)-4-(ethylsulfonyl)phenol (1134197-46-8)

Conditions	Yield
With acetic acid In tetrahydrofuran at 20 - 100℃; for 1.58333h; Microwave;	66%
With acetic acid In dichloromethane at 100℃; Microwave irradiation;

Quinoline-6-carboxylic acid (10349-57-2) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 5-(ethylsulfonyl)-2-(quinolin-6-yl)benzo[d]oxazole (1118623-69-0)

Conditions	Yield
With polyphosphoric acid Heating;	63%

C18H23NO2 + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → C26H31N3O5S

Conditions	Yield
Stage #1: 2-amino-4-(ethylsulfonyl)phenol With hydrogenchloride; sodium nitrite In water at 0℃; for 2h; Stage #2: C18H23NO2 With sodium hydroxide In water at 0℃; for 2h; pH=11;	59.5%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + Ethyl 2-bromopropionate (535-11-5, 41978-69-2) → 3,4-dihydro-6-ethylsulfonyl-2-methyl-3-oxo-2H-1,4-benzoxazine

Conditions	Yield
With 1-methyl-pyrrolidin-2-one; 1,8-diazabicyclo[5.4.0]undec-7-ene at 180℃; for 0.05h; microwave irradiation;	57%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + acetylacetone (123-54-6) → (3Z)-4-(5-ethylsulfonyl-2-hydroxyanilino)pent-3-en-2-one (1433862-60-2)

Conditions	Yield
In ethanol for 1h; Reflux;	55%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + benzoic acid (65-85-0) → 5-(ethylsulfonyl)-2-phenylbenzo[d]oxazole

Conditions	Yield
With polyphosphoric acid Heating;	52%
With PPA for 2.5h; Heating;	42%
With polyphosphoric acid for 2.5h;	42%

2,3-dichlorbenzoic acid (50-45-3) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 2-(2,3-dichlorophenyl)-5-(ethylsulfonyl)benzo[d]oxazole

Conditions	Yield
With polyphosphoric acid Heating;	50%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + 3-chlorobenzoate (535-80-8) → 2-(3-chlorophenyl)-5-(ethylsulfonyl)benzo[d]oxazole

Conditions	Yield
With polyphosphoric acid Heating;	49%

indan-5-carboxylic acid (65898-38-6) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 2-(2,3-dihydro-1H-inden-5-yl)-5-(ethylsulfonyl)benzo[d]oxazole (1118624-48-8)

Conditions	Yield
With polyphosphoric acid Heating;	47%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + para-chlorobenzoic acid (74-11-3) → 2-(4-chlorophenyl)-5-(ethylsulfonyl)benzo[d]oxazole

Conditions	Yield
With polyphosphoric acid Heating;	42%
With PPA for 2.5h; Heating;	36%

5-fluoroindole-2-carboxylic acid (399-76-8) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 5-fluoro-1H-indole-2-carboxylic acid-(5-ethanesulfonyl-2-hydroxy-phenyl)-amide (783369-84-6)

Conditions	Yield
With hydrogenchloride; triethanolamine; (benzotriazo-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate In tetrahydrofuran; ethyl acetate	40%

4-Fluorobenzoic acid (456-22-4) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → C15H12FNO3S (1045739-15-8)

Conditions	Yield
With PPA for 2.5h; Heating;	38%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + o-fluoro-benzoic acid (445-29-4) → C15H12FNO3S (1045739-26-1)

Conditions	Yield
With PPA for 2.5h; Heating;	38%

1,4-butenediol (6117-80-2) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 6-ethanesulfonyl-2-vinyl-3,4-dihydro-2H-benzo[1,4]oxazine

Conditions	Yield
With titanium(IV) isopropylate; molecular sieve; triphenylphosphine; palladium(II) acetylacetonate In benzene for 6h; Heating;	37%

p-Toluic acid (99-94-5) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 5-(ethylsulfonyl)-2-p-tolylbenzo[d]oxazole

Conditions	Yield
With PPA for 2.5h; Heating;	37%

4-biphenyl-carboxylic acid chloride (14002-51-8) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 2-(biphenyl-4-yl)-5-(ethylsulfonyl)benzo[d]oxazole

Conditions	Yield
In 1,4-dioxane at 210℃; for 0.25h; Microwave irradiation;	36%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + naphthalene-1-carbonic acid chloride (879-18-5) → 5-(ethylsulfonyl)-2-(naphthalen-1-yl)benzo[d]oxazole

Conditions	Yield
In 1,4-dioxane at 210℃; for 0.25h; Microwave irradiation;	36%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + 2-Bromoacetyl bromide (598-21-0) → 6-(ethylsulfonyl)-2H-1,4-benzoxazin-3(4H)-one

Conditions	Yield
With caesium carbonate In N,N-dimethyl-formamide at 0 - 20℃;	35%
With caesium carbonate In N,N-dimethyl-formamide

5-chloro-1H-Indole-2-carboxylic acid (10517-21-2) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 5-chloro-1H-indole-2-carboxylic acid-(5-ethanesulfonyl-2-hydroxy-phenyl)-amide (783369-83-5)

Conditions	Yield
With hydrogenchloride; triethanolamine; (benzotriazo-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate In tetrahydrofuran; ethyl acetate	35%

p-ethylbenzoic acid (619-64-7) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 5-ethylsulphonyl-2-(p-ethylphenyl)benzoxazole (1045739-18-1)

Conditions	Yield
With PPA for 2.5h; Heating;	35%
With PPA	35%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + 2-bromobenzoic-acid (88-65-3) → C15H12BrNO3S (524945-77-5)

Conditions	Yield
With PPA for 2.5h; Heating;	35%

quinoline-2-carboxylic acid (93-10-7) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 5-(ethylsulfonyl)-2-(quinolin-2-yl)benzo[d]oxazole

Conditions	Yield
With polyphosphoric acid Heating;	35%

2-amino-4-(ethylsulfonyl)phenol (43115-40-8) + ortho-chlorobenzoic acid (118-91-2) → 2-(2-chlorophenyl)-5-(ethylsulfonyl)benzo[d]oxazole

Conditions	Yield
With PPA for 2.5h; Heating;	34%
With polyphosphoric acid Heating;	33%

quinoxaline-6-carboxylic acid (6925-00-4) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → 5-(ethylsulfonyl)-2-(quinoxalin-6-yl)benzo[d]oxazole (1118623-71-4)

Conditions	Yield
With polyphosphoric acid Heating;	33%

4-Bromobenzoic acid (586-76-5) + 2-amino-4-(ethylsulfonyl)phenol (43115-40-8) → C15H12BrNO3S (524945-79-7)

Conditions	Yield
With PPA for 2.5h; Heating;	32%

Upstream product

• 5120-72-9 p-chlorophenyl ethyl sulfide 
• 7205-80-3 1-(ethylsulfonyl)-4-chlorobenzene 
• 84996-11-2 4-(ethylsulfonyl)-2-nitro-phenol 
• 51572-44-2 4-(ethylsulfonyl)-1-methoxy-2-nitrobenzene 
• 7205-79-0 1-(ethylsulfonyl)-4-methoxybenzene 
• 6462-50-6 sodium 4-methoxybenzenesulfinate 
• 98-68-0 4-methoxy-phenyl-sulphonyl chloride 

Downstream Products

• 874774-43-3 6-(ethylsulfonyl)-2H-1,4-benzoxazin-3(4H)-one 
• 888731-84-8 2-chloro-N-(5-ethanesulfonyl-2-hydroxyphenyl)acetamide 
• 783369-83-5 5-chloro-1H-indole-2-carboxylic acid-(5-ethanesulfonyl-2-hydroxy-phenyl)-amide 
• 783369-86-8 1H-Indole-2-carboxylic acid-(5-ethanesulfonyl-2-hydroxy-phenyl)-amide 
• 783369-87-9 5-Methoxy-1H-indole-2-carboxylic acid-(5-ethanesulfonyl-2-hydroxy-phenyl)-amide 
• 888731-85-9 6-ethanesulfonyl-3,4-dihydro-2H-benzo[1,4]oxazine 
• 945531-77-1 ezutromid 
• 1433862-60-2 (3Z)-4-(5-ethylsulfonyl-2-hydroxyanilino)pent-3-en-2-one 
• 1421257-25-1 C₂₂H₃₁N₃O₅S 
• 1118624-42-2 (E)-5-(ethylsulfonyl)-2-styrylbenzo[d]oxazole 
• 1118624-46-6 5-(ethylsulfonyl)-2-(4-phenoxyphenyl)benzo[d]oxazole 
• 1118623-36-1 5-(ethylsulfonyl)-2-(3-phenoxyphenyl)benzo[d]oxazole 
• 1193007-08-7 2-(5-(ethylsulfonyl)benzo[d]oxazol-2-yl)phenol 
• 1247007-65-3 (Z)-5-(ethylsulfonyl)-2-(1-fluoro-2-phenylvinyl)benzo[d]oxazole 

Relevant articles and documents

A 2 - amino - (4 - ethyl sulfonyl) phenol synthesis method (by machine translation)

The invention discloses a 2 - amino - (4 - ethyl sulfonyl) phenolic synthetic method, to 4 - methoxybenzene sulfonyl chloride as the starting material, by reduction, ethyl substituted, nitration, de-methyl, 2 - amino - (4 - ethyl sulfonyl) phenol to prepare five-step reaction to obtain the final product 2 - amino - (4 - ethyl sulfonyl) phenol. The present invention the used raw materials are cheap and easily obtained, mild and easy to control the process, the reaction apparatus and after treatment is simple, low cost, easy to industrial production. (by machine translation)