98-71-5

Basic information

• Product Name: 4-Hydrazinobenzenesulfonic acid
• Synonyms: p-hydrazinobenzenesulfonicacid;p-hydrazinophenylsulfonicacid;p-sulfophenylhydrazine;4-Hydrazinobenzene-P-Sulfonic Acid;4-Hydrazinobenzenesulfonicacidhemihydrate,98%;4-Hydrazinobenzeneslfonic acid;BENZENESULPHONICACID,PARA-HYDRAZINO-;PHENYLHYDRAZINE-PARA-SULPHONICACID
• CAS NO: 98-71-5
• Molecular Formula: C₆H₈N₂O₃S
• Molecular Weight: 188.2
• EINECS: 202-694-2
• Product Categories: Phenylhydrazine
• Mol File: 98-71-5.mol
• Article Data: 35

Chemical Properties

• Melting Point: 285°C
• Boiling Point: 500°C (estimate)
• Flash Point: °C
• Appearance: /solid
• Density: 1.366 (estimate)
• Refractive Index: 1.6490 (estimate)
• Storage Temp.: Refrigerator, Under Inert Atmosphere
• Solubility: DMSO (Slightly), Water (Slightly)
• PKA: -0.66±0.50(Predicted)
• Water Solubility: It is soluble in water.
• Sensitive: Hygroscopic
• Merck: 4773
• CAS DataBase Reference: 4-Hydrazinobenzenesulfonic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 4-Hydrazinobenzenesulfonic acid(98-71-5)
• EPA Substance Registry System: 4-Hydrazinobenzenesulfonic acid(98-71-5)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-36/37/39-60-37
• RIDADR: 2585
• RTECS: DB6900000
• TSCA: Yes
• Hazardous Substances Data: 98-71-5(Hazardous Substances Data)

Usage

Chemical Properties

white to light yellow crystal powde

Uses

Hemihydrate of 4-Hydrazinobenzenesulfonic Acid is used in analytical experiments to determine trace components of mixtures. Also used in the synthesis of inhibitors of coxsackievirus B3 replication. T artrazine (T007700) analog.

Uses

4-Hydrazinobenzenesulfonic Acid is used as an intermediate to manufacture pharmaceuticals, dyes and other organic synthesis. They have active applications in organic synthesis for agrochemicals, pharmaceuticals, photographic, heat stabilizers, polymerization catalysts, flame-retardants, blowing agents for plastics, explosives, and dyes.

InChI:InChI=1/C6H8N2O3S.H2O/c7-8-5-1-3-6(4-2-5)12(9,10)11;/h1-4,8H,7H2,(H,9,10,11);1H2

Synthetic route

4-sulfobenzenediazonium (2154-66-7) → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
Stage #1: 4-sulfobenzenediazonium With sodium sulphite-heptahydrate In water at 0 - 5℃; for 2h; Stage #2: With hydrogenchloride In water for 0.5h;	96%
With sulfuric acid; sodium sulfite at 0 - 5℃;	95%

4-aminobenzene sulfonic acid (121-57-3) → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
Stage #1: 4-aminobenzene sulfonic acid With sulfuric acid; sodium carbonate; sodium nitrite In water at 5℃; Stage #2: With hydrogenchloride; sodium sulfite In water at 5℃; Reflux;	85%
Stage #1: 4-aminobenzene sulfonic acid With sulfuric acid; sodium carbonate; sodium nitrite In water at 12℃; Cooling with ice; Stage #2: With sodium sulfite In water at 5℃; Heating; Stage #3: With hydrogenchloride; zinc In water at 20℃; for 12h;	74%
Diazotization.Behandeln mit Na2SO3 und Spalten mit Salzsaeure;

4-Sulfo-benzenediazonium; hydrogen sulfate → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
Stage #1: 4-Sulfo-benzenediazonium; hydrogen sulfate With sodium sulfite In water Heating / reflux; Stage #2: With hydrogenchloride In water	85%

4-diazobenzenesulfonic acid (305-80-6) → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
With potassium sulfite Kochen mit konz. Salzsaeure;
With sodium dithionite Hydrolyse des Reaktionsprodukts mit kochender Salzsaeure;

4-nitroamino-benzenesulfonic acid (61734-81-4) → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
With sodium amalgam

ethanol (64-17-5) + 4-[N'-(α-hydroxy-3,4-methylenedioxy-benzyl)-hydrazino]-benzenesulfonic acid → piperonal (120-57-0) + 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
allmaehliche Zersetzung;

4-[N'-(α-hydroxy-3,4-methylenedioxy-benzyl)-hydrazino]-benzenesulfonic acid + acetic acid (64-19-7) → piperonal (120-57-0) + 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
schnelle Zersetzung;

phenylhydrazine (100-63-0) → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
With sulfuric acid at 80 - 100℃;

4-[N'-(α-hydroxy-3,4-methylenedioxy-benzyl)-hydrazino]-benzenesulfonic acid + water (7732-18-5) → piperonal (120-57-0) + 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
allmaehliche Zersetzung;

4-[N'-(α-hydroxy-3,4-methylenedioxy-benzyl)-hydrazino]-benzenesulfonic acid + hot water → piperonal (120-57-0) + 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
schnelle Zersetzung;

4-[N'-(α-hydroxy-3,4-methylenedioxy-benzyl)-hydrazino]-benzenesulfonic acid + mineral acid → piperonal (120-57-0) + 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
schnelle Zersetzung;

sulfuric acid (7664-93-9) + phenylhydrazine (100-63-0) → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
unter Kuehlung und anschl. Erwaermen auf 80-100grad;

disodium-salt of/the/ 4-cis-azo>-benzene-sulfonic acid-(1) → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
With sodium hydroxide Reduktion an einer Quecksilber-Kathode;

disodium-salt of/the/ 4-trans-azo>-benzene-sulfonic acid-(1) → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
With sodium hydroxide Reduktion an einer Quecksilber-Kathode;

4-aminobenzene sulfonic acid (121-57-3) + hydroxylamine-O-sulfonic acid → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
With sodium hydroxide

p-diazobenzenesulfonate sodium → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
With sodium amalgam

potassium salt of/the/ phenylhydrazine-4.α.β-trisulfonic acid → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
With hydrogenchloride

potassium salt of/the/ phenylhydrazine-4.β-disulfonic acid → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
With hydrogenchloride

hydrogenchloride (7647-01-0) + 4-diazobenzenesulfonic acid (305-80-6) + diluted alkali + potassium sulfite → 4-hydrazino-benzenesulfonic acid (98-71-5)

4-nitroamino-benzenesulfonic acid (61734-81-4) + sodium amalgam + alkali → 4-hydrazino-benzenesulfonic acid (98-71-5)

(E)-4-hydroxyazo-benzenesulfonic acid ; disodium-salt (118834-04-1) + sodium amalgam + alkali → 4-hydrazino-benzenesulfonic acid (98-71-5)

4-(N'-sulfo-hydrazino)-benzenesulfonic acid ; dipotassium-salt + strong hydrochloric acid → 4-hydrazino-benzenesulfonic acid (98-71-5)

4-(N,N'-disulfo-hydrazino)-benzenesulfonic acid ; tripotassium-salt trihydrate + hydrochloric acid → 4-hydrazino-benzenesulfonic acid (98-71-5) + sulfuric acid

HSO3(2-) + 4-sulfobenzenediazonium (2154-66-7) → 4-hydrazino-benzenesulfonic acid (98-71-5)

Conditions	Yield
In not given
In not given

3-methyl-butan-2-one (563-80-4) + 4-hydrazino-benzenesulfonic acid (98-71-5) → 2,3,3-trimethylindole-5-sulfonic acid (132557-72-3)

Conditions	Yield
With acetic acid for 3h; Concentration; Fischer Indole Synthesis; Reflux;	97%
With acetic acid for 14h; Reflux;	94%
With acetic acid at 120℃; Fischer Indole Synthesis;	94%

benzaldehyde (100-52-7) + 4-hydrazino-benzenesulfonic acid (98-71-5) → hydrazone 4-[(2Z)-2-benzylidenehydrazinyl]benzenesulfonic acid

Conditions	Yield
Stage #1: 4-hydrazino-benzenesulfonic acid With sodium hydroxide In water at 45℃; for 0.5h; pH=10; Stage #2: benzaldehyde In water at 55 - 60℃; for 3.5h;	97%
With 1-deoxy-1-(methylamino)-D-glucitol In ethanol; water at 20℃; for 0.5h;	96%
Stage #1: 4-hydrazino-benzenesulfonic acid With sodium hydroxide In water at 45℃; for 0.5h; pH=Ca. 10; Stage #2: benzaldehyde at 55 - 60℃; for 3h;

indole-2,3-dione (91-56-5) + 2-aminoacetophenone (551-93-9) + 4-hydrazino-benzenesulfonic acid (98-71-5) → C22H15N3O4S

Conditions	Yield
In ethanol for 0.3h; Inert atmosphere; Reflux;	94%

5-fluoro-1H-indole-2,3-dione (443-69-6) + 2-aminoacetophenone (551-93-9) + 4-hydrazino-benzenesulfonic acid (98-71-5) → C22H14FN3O4S

Conditions	Yield
In ethanol for 0.25h; Inert atmosphere; Reflux;	94%

5-Bromo-1H-indole-2,3-dione (87-48-9) + 2-aminoacetophenone (551-93-9) + 4-hydrazino-benzenesulfonic acid (98-71-5) → C22H14BrN3O4S

Conditions	Yield
In ethanol for 0.266667h; Inert atmosphere; Reflux;	93%

2-aminoacetophenone (551-93-9) + 4-hydrazino-benzenesulfonic acid (98-71-5) + acenaphthene quinone (82-86-0) → C26H16N2O4S

Conditions	Yield
In ethanol for 0.366667h; Inert atmosphere; Reflux;	92%

3-methyl-butan-2-one (563-80-4) + 4-hydrazino-benzenesulfonic acid (98-71-5) → potassium 2,3,3-trimethylindole-5-sulfonate

Conditions	Yield
Stage #1: 3-methyl-butan-2-one; 4-hydrazino-benzenesulfonic acid With acetic acid for 4h; Reflux; Stage #2: With potassium hydroxide In methanol; propan-1-ol at 20℃; for 24h;	90%
Stage #1: 3-methyl-butan-2-one; 4-hydrazino-benzenesulfonic acid With acetic acid for 3h; Reflux; Stage #2: With potassium hydroxide In methanol; isopropyl alcohol Cooling with ice; Sonication;	80%
Stage #1: 3-methyl-butan-2-one; 4-hydrazino-benzenesulfonic acid In acetic acid at 105℃; for 2.33333h; Heating / reflux; Stage #2: With potassium acetate In methanol; acetic acid	77%

1-Methyl-4-piperidone (1445-73-4) + 2-aminoacetophenone (551-93-9) + 4-hydrazino-benzenesulfonic acid (98-71-5) → C20H21N3O3S

Conditions	Yield
In ethanol for 0.466667h; Inert atmosphere; Reflux;	90%

2-aminoacetophenone (551-93-9) + 4-hydrazino-benzenesulfonic acid (98-71-5) + 3,4-dihydronaphthalene-1(2H)-one (529-34-0) → C24H20N2O3S

Conditions	Yield
In ethanol for 0.4h; Inert atmosphere; Reflux;	90%

5-nitroisatin (611-09-6) + 2-aminoacetophenone (551-93-9) + 4-hydrazino-benzenesulfonic acid (98-71-5) → C22H14N4O6S

Conditions	Yield
In ethanol for 0.416667h; Inert atmosphere; Reflux;	89%

5-methyl-indole-2,3-dione (608-05-9) + 2-aminoacetophenone (551-93-9) + 4-hydrazino-benzenesulfonic acid (98-71-5) → C23H17N3O4S

Conditions	Yield
In ethanol for 0.4h; Inert atmosphere; Reflux;	88%

4-hydrazino-benzenesulfonic acid (98-71-5) + 3-iminobutyronitrile (1118-60-1) → 5-amino-3-methyl-1-(4-sulfophenyl)pyrazole (69075-48-5)

Conditions	Yield
Stage #1: 4-hydrazino-benzenesulfonic acid; 3-iminobutyronitrile for 1h; Condensation; Heating; Stage #2: With hydrogenchloride for 2h; Cyclization; Heating;	85.6%

2-furancarbonyl chloride (527-69-5) + cyclohexanone (108-94-1) + 4-hydrazino-benzenesulfonic acid (98-71-5) → 9-(furan-2-carbonyl)-6,7,8,9-tetrahydro-5H-carbazole-3-sulfonic acid

Conditions	Yield
Stage #1: 4-hydrazino-benzenesulfonic acid With polystyrene aldehyde resin; triethylamine In 1,2-dichloro-ethane at 45℃; Stage #2: 2-furancarbonyl chloride With pyridine at 80℃; Stage #3: cyclohexanone With trifluoroacetic acid In 1,2-dichloro-ethane at 70℃;	85%

4-hydrazino-benzenesulfonic acid (98-71-5) + 2-(2-hydroxyphenyl)-4H-benzo[e][1,3]oxazin-4-one (1218-69-5) → 4-[3,5-bis(2-hydroxyphenyl)-1H-1,2,4-triazol-1-yl]benzenesulfonic acid

Conditions	Yield
With triethylamine In ethanol for 20h; Heating;	85%

5-methyl-6-oxoheptane-1-sulphonic acid (688339-30-2) + 4-hydrazino-benzenesulfonic acid (98-71-5) → 2,3-dimethyl-3-(4-sulphobutyl)-3H-indole-5-sulphonicacid (688339-34-6)

Conditions	Yield
With acetic acid for 6h; Reflux;	85%
With acetic acid for 6h; Heating / reflux;
With acetic acid for 6h; Heating / reflux;

4,4,4-trifluoro-1-(4-methylphenyl)butane-1,3-dione (720-94-5) + 4-hydrazino-benzenesulfonic acid (98-71-5) → 4-(5-(p-tolyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl)benzenesulfinic acid

Conditions	Yield
With hydrogenchloride In ethanol Reflux;	85%

6-methyl-7-oxooctanoic acid (99183-34-3) + 4-hydrazino-benzenesulfonic acid (98-71-5) → potassium 3-(4-carboxybutyl)-2,3-dimethylindolenine-5-sulfonate (1072069-89-6)

Conditions	Yield
Stage #1: 6-methyl-7-oxooctanoic acid; 4-hydrazino-benzenesulfonic acid With acetic acid for 8h; Reflux; Stage #2: With potassium hydroxide In methanol; diethyl ether; isopropyl alcohol	83%
Stage #1: 6-methyl-7-oxooctanoic acid; 4-hydrazino-benzenesulfonic acid In acetic acid for 8h; Reflux; Stage #2: With potassium hydroxide In methanol; diethyl ether; isopropyl alcohol	83%

4-hydrazino-benzenesulfonic acid (98-71-5) + 2-hydroxynaphthalene-1-carbaldehyde (708-06-5) → C17H14N2O4S

Conditions	Yield
With toluene-4-sulfonic acid In ethanol at 80℃;	83%

4,4,4-trifluoro-1-(4-methylphenyl)butane-1,3-dione (720-94-5) + 4-hydrazino-benzenesulfonic acid (98-71-5) → 4-(5-p-methylphenyl-3-trifluoromethyl-pyrazol-1-yl)-benzenesulfonic acid (921617-76-7)

Conditions	Yield
With hydrogenchloride In ethanol; water at 20℃; for 8h; Heating / reflux;	82%
With hydrogenchloride In ethanol for 8h; Heating;	82%

C35H44N2O5S3 + 4-hydrazino-benzenesulfonic acid (98-71-5) → C41H49N4O7S4(1-)*H4N(1+)

Conditions	Yield
Stage #1: C35H44N2O5S3 With hydrogenchloride In methanol at 90℃; Stage #2: 4-hydrazino-benzenesulfonic acid In ethanol; water at 90℃; for 16h; Inert atmosphere;	82%

3-methyl-butan-2-one (563-80-4) + 4-hydrazino-benzenesulfonic acid (98-71-5) → ammonium 2,3,3-trimethyl-3H-indole-5-sulfonate

Conditions	Yield
With acetic acid at 118℃; for 18h; Inert atmosphere;	80%
With acetic acid at 118℃; for 18h; Inert atmosphere;	80%

3-Bromophthalide (6940-49-4) + 4-hydrazino-benzenesulfonic acid (98-71-5) → 1'-(1-oxophthalazin-2(1H)-yl)benzenesulfonic acid

Conditions	Yield
Stage #1: 3-Bromophthalide With hydrogenchloride In water for 2h; Reflux; Stage #2: 4-hydrazino-benzenesulfonic acid In water at 20℃; for 2h;	76%

rac-methyl 6-methyl-7-oxooctanoate (5601-58-1) + 4-hydrazino-benzenesulfonic acid (98-71-5) → sodium 3-(5-methoxy-5-oxopentyl)-2,3-dimethyl-3H-indole-5-sulfonate

Conditions	Yield
Stage #1: rac-methyl 6-methyl-7-oxooctanoate; 4-hydrazino-benzenesulfonic acid With acetic acid for 4h; Fischer Indole Synthesis; Reflux; Stage #2: With sodium carbonate In methanol at 20℃; for 15h;	76%

benzaldehyde (100-52-7) + 4-hydrazino-benzenesulfonic acid (98-71-5) → benzaldehyde (4-sulfophenyl)hydrazone

Conditions	Yield
With acetic acid In water at 60℃; for 3h; pH=3;	72%

3-methyl-butan-2-one (563-80-4) + 4-hydrazino-benzenesulfonic acid (98-71-5) → 2,3,3,-trimethylindoleninium-5-sulfonate potassium salt

Conditions	Yield
Stage #1: 3-methyl-butan-2-one; 4-hydrazino-benzenesulfonic acid With acetic acid at 115℃; for 4h; Inert atmosphere; Stage #2: With potassium hydroxide In methanol; isopropyl alcohol	69.5%

4-methyl-5-oxohexane sulfonic acid (952292-10-3) + 4-hydrazino-benzenesulfonic acid (98-71-5) → 2,3-dimethyl-3-(3-sulfopropyl)indoleninium-5-sulfonate potassium salt

Conditions	Yield
Stage #1: 4-methyl-5-oxohexane sulfonic acid; 4-hydrazino-benzenesulfonic acid With acetic acid at 115℃; for 30h; Inert atmosphere; Reflux; Stage #2: With potassium hydroxide In methanol; isopropyl alcohol at 50℃; for 18h;	68.4%

2-Thiophenecarbonyl chloride (5271-67-0) + cyclohexanone (108-94-1) + 4-hydrazino-benzenesulfonic acid (98-71-5) → 9-(thiophene-2-carbonyl)-6,7,8,9-tetrahydro-5H-carbazole-3-sulfonic acid

Conditions	Yield
Stage #1: 4-hydrazino-benzenesulfonic acid With polystyrene aldehyde resin; triethylamine In 1,2-dichloro-ethane at 45℃; Stage #2: 2-Thiophenecarbonyl chloride With pyridine at 80℃; Stage #3: cyclohexanone With trifluoroacetic acid In 1,2-dichloro-ethane at 70℃;	66%

Upstream product

• 515-74-2 4-Amino-benzenesulfonic acid monosodium salt 
• 7440-66-6 ZINC 
• 7631-90-5 Sodium bisulfite 
• 61790-53-2 Celite 

Downstream Products

• 1934-21-0 Acid Yellow 23 
• 18336-39-5 4-(1H-PYRAZOL-1-YL)BENZENESULFONYL CHLORIDE 

Recommend Products

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• 674-82-8  4-methyleneoxetan-2-one 
• 1122-62-9  2-acetylpyridine 
• 120-57-0  piperonal 
• 16432-90-9  4-(3,4-dihydroxy-phenyl-trans-azo)-benzenesulfonic acid 
• 15448-58-5  2,3-epoxy-2,3-dihydro-1,4-naphthoquinone 
• 723-89-7  1-phenyl-indole-2,3-dione 
• 28284-05-1  N-benzoylisatin 
• 305-80-6  4-diazobenzenesulfonic acid 
• 64-17-5  ethanol 
• 64-19-7  acetic acid