121-03-9

Basic information

• Product Name: 2-Methyl-5-nitrobenzenesulfonic acid
• Synonyms: 2-Methyl-5-nitrobenzenesalfonicacid;2-methyl-5-nitro-benzenesulfonicaci;2-toluenesulfonicacid,5-nitro;4-Nitro-o-toluenesulfonicacid;4-nitrotoluene-2-sulphonicacid;5-nitro-2-methylbenzenesulfonicacid;5-nitro-o-toluenesulfonicaci;5-nitro-o-toluenesulfonicacid
• CAS NO: 121-03-9
• Molecular Formula: C₇H₇NO₅S
• Molecular Weight: 217.2
• EINECS: 204-445-3
• Product Categories: Intermediates of Dyes and Pigments
• Mol File: 121-03-9.mol
• Article Data: 7

Chemical Properties

• Melting Point: 135°C
• Boiling Point: 500°C (rough estimate)
• Appearance: /
• Density: 1.6040 (rough estimate)
• Vapor Pressure: 0Pa at 20℃
• Refractive Index: 1.6100 (estimate)
• Storage Temp.: Sealed in dry,Room Temperature
• Solubility: Methanol (Slightly), Water (Slightly)
• PKA: -1.14±0.33(Predicted)
• Water Solubility: 667g/L at 23℃
• CAS DataBase Reference: 2-Methyl-5-nitrobenzenesulfonic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 2-Methyl-5-nitrobenzenesulfonic acid(121-03-9)
• EPA Substance Registry System: 2-Methyl-5-nitrobenzenesulfonic acid(121-03-9)

Safety Data

• Hazard Codes: Xn
• Statements: 34-41-43-36-22
• Safety Statements: 26-36/37/39-39-36/37
• RIDADR: 3261
• RTECS: DB7175000
• HazardClass: 8
• PackingGroup: III
• Hazardous Substances Data: 121-03-9(Hazardous Substances Data)

Usage

Uses

5-Nitro-o-toluenesulfonic Acid is a precursor to 4,4''-dinitrostilbene-2,2''-disulfonic acid in fluorescent whitener.

Definition

ChEBI: The arenesulfonic acid that is toluene-2-sulfonic acid bearing a nitro substituent at C-4.

Flammability and Explosibility

Nonflammable

InChI:InChI=1/C7H7NO5S/c1-5-4-6(8(9)10)2-3-7(5)14(11,12)13/h2-4H,1H3,(H,11,12,13)

Synthetic route

1-methyl-4-nitrobenzene (99-99-0) → 4-nitrotoluene-2-sulfonic acid (121-03-9)

Conditions	Yield
With sulfuric acid at 75℃; for 1h;	96%
With sulfuric acid at 90℃; for 1h; Substitution;	35%
With sulfuric acid

2,2-dimethyl-propanol-1 (75-84-3) + 2-methyl-5-nitrobenzene-1-sulfonyl chloride (121-02-8) → 4-nitrotoluene-2-sulfonic acid (121-03-9)

Conditions	Yield
With pyridine In 1,4-dioxane	55%

o-toluenesulfonic acid (88-20-0) → 4-nitrotoluene-2-sulfonic acid (121-03-9)

Conditions	Yield
With nitric acid In water at -5 - 80℃; for 6h;

toluene (108-88-3) → 4-nitrotoluene-2-sulfonic acid (121-03-9)

Conditions	Yield
Multi-step reaction with 2 steps 1: nitric acid / man faellt mit Wasser und schuettelt das gefaellte Oel mit Ammoniak 2: sulfuric acid View Scheme
Multi-step reaction with 2 steps 1: sulfuric acid / -5 - 0 °C / Electric arc 2: nitric acid / water / 6 h / -5 - 80 °C View Scheme

4-methylisopropylbenzene (99-87-6) → 4-nitrotoluene-2-sulfonic acid (121-03-9) + 6-nitro-p-cymene-sulfonic acid-(2)

Conditions	Yield
With sulfuric acid Behandeln des Reaktionsgemisches mit Salpetersaeure bei 40-60grad;
With sulfuric acid Behandeln des Reaktionsgemisches mit Salpeterschwefelsaeure oder Nitraten;

toluene (108-88-3) → 4-methyl-3-nitro-benzenesulfonic acid (97-06-3) + 4-nitrotoluene-2-sulfonic acid (121-03-9)

Conditions	Yield
With sulfuric acid dann Zufuegen unter Umschuetteln Salpetersaeure, bis keine Temperaturerhoehung mehr stattfindet; Trennung der Saeuren in Form ihrer Calciumsalze; das Salz der 2-Nitro-toluol-sulfonsaeure-(4) ist das schwerer loesliche;
With sulfuric acid durch Eintragen von Salpetersaeure in das enstandene Gemisch von Toluolsulfonsaeuren;

4-methylisopropylbenzene (99-87-6) → 4-nitrotoluene-2-sulfonic acid (121-03-9) + 5-isopropyl-2-methyl-3-nitro-benzenesulfonic acid (859185-51-6)

Conditions	Yield
With sulfuric acid Abkuehlen auf 40grad und anscliessendes Eintragen von Salpetersaeure;

1-methyl-4-nitrobenzene (99-99-0) + sulfur trioxide sulfuric acid-mixtures → 4-nitrotoluene-2-sulfonic acid (121-03-9)

Conditions	Yield
at 0 - 45℃; Rate constant;

1-methyl-4-nitrobenzene (99-99-0) + sulfuric acid (7664-93-9) + iodine (7553-56-2) → 4-nitrotoluene-2-sulfonic acid (121-03-9)

Conditions	Yield
at 140℃;

1-methyl-4-nitrobenzene (99-99-0) + sulfur trioxide sulfuric acid-mixtures + potassium sulfate + barium sulfate → 4-nitrotoluene-2-sulfonic acid (121-03-9)

Conditions	Yield
Rate constant;

4-methylisopropylbenzene (99-87-6) + sulfuric acid (7664-93-9) → 4-nitrotoluene-2-sulfonic acid (121-03-9) + 6-nitro-p-cymene-sulfonic acid-(2)

Conditions	Yield
Behandeln des Reaktionsprodukts mit Salpetersaeure bei 40-60grad;

1-methyl-4-nitrobenzene (99-99-0) + sulfuric acid (7664-93-9) → 4-nitrotoluene-2-sulfonic acid (121-03-9)

4,4'-dinitrostilbene 2,2'-disulfonic acid (1211962-72-9) + aqueous KOH-solution → formic acid (64-18-6) + 4-nitrotoluene-2-sulfonic acid (121-03-9)

4-nitrotoluene-2-sulfonic acid (121-03-9) → 4-amino-toluene-2-sulfonic acid (118-88-7)

Conditions	Yield
Stage #1: 4-nitrotoluene-2-sulfonic acid With iron(II,III) oxide; tetrabutylammomium bromide; iron; iron(II) chloride In water at 110 - 120℃; pH=7.5 - 8; Stage #2: With ammonium hydroxide In water at 85 - 90℃; for 1.5h; pH=11.2 - 11.5; Stage #3: With hydrogenchloride In water pH=2 - 3;	98.75%
With hydrogen sulfide; ammonia

4-nitrotoluene-2-sulfonic acid (121-03-9) → 4,4'-dinitrostilbene 2,2'-disulfonic acid (1211962-72-9)

Conditions	Yield
With sodium hydroxide; sodium hypochlorite In water; diethylene glycol at 85℃; for 0.166667h;	93%
With chlorine; sodium hydroxide In water at 35 - 45℃; for 1h; Reagent/catalyst; Electric arc;	85.5%
With sodium hypochlorite

4-nitrotoluene-2-sulfonic acid (121-03-9) → 4,4'-diaminostilbene-2,2'-disulfonic acid (81-11-8)

Conditions	Yield
With hydrazine hydrate; potassium hydroxide In water; diethylene glycol for 3h; Reflux;	73%
With alkali Reduktion der erhaltenen Farbstoffe mit Zinn bezw. Zinnchloruer und Salzsaeure;
Multi-step reaction with 2 steps 1: hypochlorite 2: TiCl3; hydrochloric acid View Scheme

4-nitrotoluene-2-sulfonic acid (121-03-9) → 2-carboxy-5-nitrobenzenesulfonic acid (22952-26-7)

Conditions	Yield
With potassium permanganate; water at 115℃; for 5h;	72%
With potassium permanganate In water at 115℃; for 5h;	72%
Stage #1: 4-nitrotoluene-2-sulfonic acid With potassium permanganate; sodium hydroxide In water at 90℃; for 3h; Stage #2: With hydrogenchloride In water pH=1 - 2;

4-nitrotoluene-2-sulfonic acid (121-03-9) → 4,4'-dinitrostilbene 2,2'-disulfonic acid (1211962-72-9) + disodium 4,4'-dinitrobibenzyl-2,2'-disulfonate (6268-17-3)

Conditions	Yield
With sodium hypochlorite In sodium hydroxide at 65℃; for 0.416667h;	A n/a B 65%

pyrrolidine (123-75-1) + 4-nitrotoluene-2-sulfonic acid (121-03-9) + 3,4,5-trimethoxy-benzaldehyde (86-81-7) → (E)‑2‑(3,4,5‑trimethoxystyryl)‑5‑nitrobenzenesulfonate pyrrolidinium

Conditions	Yield
Stage #1: 4-nitrotoluene-2-sulfonic acid With sodium carbonate In dimethyl sulfoxide at 20℃; for 0.166667h; Stage #2: pyrrolidine; 3,4,5-trimethoxy-benzaldehyde In dimethyl sulfoxide at 94℃; for 48h;	53.26%

ethanol (64-17-5) + 4-nitrotoluene-2-sulfonic acid (121-03-9) + (R)-5-isopropyl-2-methylcyclohexa-1,3-diene (4221-98-1) → 1-methyl-4-isopropyl-1,3-cyclohexadiene (99-86-5)

Conditions	Yield
Kinetics;

4-nitrotoluene-2-sulfonic acid (121-03-9) → 2-chloro-4-nitrotoluene (121-86-8)

Conditions	Yield
With copper dichloride

4-nitrotoluene-2-sulfonic acid (121-03-9) → 2-bromo-4-nitrotoluene (7745-93-9)

Conditions	Yield
With copper(ll) bromide

4-nitrotoluene-2-sulfonic acid (121-03-9) → 4-amino-toluene-2-sulfonic acid (118-88-7) + 4,4'-azo-bis-toluene-2-sulfonic acid

Conditions	Yield
With potassium hydroxide; zinc

4-nitrotoluene-2-sulfonic acid (121-03-9) → 2,4-dinitrotoluene-6-sulfonic acid (133-62-0)

Conditions	Yield
With nitric acid
With sulfuric acid; nitric acid

4-nitrotoluene-2-sulfonic acid (121-03-9) → 4-nitrobenzaldehyde-2-sulphonic acid (43099-64-5)

Conditions	Yield
With sodium hypochlorite
With hypobromite
Multi-step reaction with 2 steps 1: hypochlorite 2: KMnO4 View Scheme

4-nitrotoluene-2-sulfonic acid (121-03-9) → 4,4'-dinitrobibenzyl-2,2'-disulfonic acid (6404-60-0)

Conditions	Yield
With sodium hydroxide
With sodium hypochlorite at 40 - 70℃;

4-nitrotoluene-2-sulfonic acid (121-03-9) → 4,4'-azo-bis-toluene-2-sulfonic acid

Conditions	Yield
With potassium hydroxide; zinc
Electrolysis.in alkal. Loesung;

4-nitrotoluene-2-sulfonic acid (121-03-9) → 5-amino-2-formyl-benzenesulfonic acid (69851-86-1)

Conditions	Yield
With sulfuric acid; sulfur
With sulfur

4-nitrotoluene-2-sulfonic acid (121-03-9) → 4-amino-toluene-2-sulfonic acid (118-88-7) + 4,4'-diaminostilbene-2,2'-disulfonic acid (81-11-8)

Conditions	Yield
With alkaline solution; zinc
With alkaline solution; zinc

4-nitrotoluene-2-sulfonic acid (121-03-9) + furan-2,3,5(4H)-trione pyridine (1:1) + p,p'-diaminobiphenyl (92-87-5) → Chicago orange

4-nitrotoluene-2-sulfonic acid (121-03-9) + copper (II)-chloride → 2-chloro-4-nitrotoluene (121-86-8)

4-nitrotoluene-2-sulfonic acid (121-03-9) + copper (II)-bromide → 2-bromo-4-nitrotoluene (7745-93-9)

4-nitrotoluene-2-sulfonic acid (121-03-9) + hydrogen sulfide (7783-06-4) + ammonia (7664-41-7) → 4-amino-toluene-2-sulfonic acid (118-88-7)

hydrogenchloride (7647-01-0) + 4-nitrotoluene-2-sulfonic acid (121-03-9) + tin → 4-amino-toluene-2-sulfonic acid (118-88-7)

4-nitrotoluene-2-sulfonic acid (121-03-9) + zinc + KOH-solution → 4-amino-toluene-2-sulfonic acid (118-88-7)

Conditions	Yield
liefert erst 4.4'-Dimethyl-azobenzol-disulfonsaeure-(3.3');

Upstream product

• 88-20-0 o-toluenesulfonic acid 
• 75-84-3 2,2-dimethyl-propanol-1 
• 121-02-8 2-methyl-5-nitrobenzene-1-sulfonyl chloride 
• 1211962-72-9 4,4'-dinitrostilbene 2,2'-disulfonic acid 
• 99-87-6 4-methylisopropylbenzene 
• 99-99-0 1-methyl-4-nitrobenzene 
• 7664-93-9 sulfuric acid 
• 7553-56-2 iodine 
• 108-88-3 toluene 

Downstream Products

• 81-11-8 4,4'-diaminostilbene-2,2'-disulfonic acid 
• 527-76-4 4-amino-2-sulfobenzoic acid 
• 588-59-0 stilbene 
• 1376763-22-2 C₁₈H₁₄N₈O₇S 
• 1376763-63-1 C₁₉H₁₆N₄O₆S 
• 1376763-25-5 C₂₀H₁₉N₅O₅S 
• 1376763-37-9 C₁₃H₁₃N₃O₅S 
• 1262794-01-3 tert-butyl N-3,5-dinitrobenzylcarbamate 
• 22952-26-7 2-carboxy-5-nitrobenzenesulfonic acid 
• 6272-71-5 4',4'''-dinitro-4,4''-azo-bis-stilbene-2,2'-disulfonic acid ; tetrasodium-compound 
• 5344-48-9 potassium 5-nitro-2-carboxybenzenesulfonate 
• 5136-34-5 6,6'-(ethane-1,2-diyl)bis(3-aminobenzenesuIfonic acid) 
• 28097-15-6 trans-stilbene-disulfonic acid-(2,2') 
• 56919-17-6 4-bromo-toluene-2-sulfonic acid 

Relevant articles and documents

Modified methods for the synthesis of triazinyl fluorescent brightener intermediates

The production of triazinyl fluorescent brightener intermediates in high yields is described. The method involves a simplified work-up for the preparation of 4-nitro-toluene-2-sulfonic acid and the use of diethylene glycol instead of water in the preparation of 4,4′-dinitrostilbene-2,2′- disulfonic acid.

P-nitrotoluene-2-sulfonic acid continuous synthesis method

Disclosed is a p-nitrotoluene-2-sulfonic acid continuous synthesis method. The p-nitrotoluene-2-sulfonic acid continuous synthesis method comprises melting or dissolving p-nitrotoluene in organic solvent or inorganic solvent, and inletting the melt of solution together with sulfur trioxide mixed gas into a film sulfonation reactor for sulfonation reaction, filtering liquid reaction products containing the inorganic solvent to remove the inorganic solvent and then feeding the reaction products into an ageing tank, or directly feeding the solvent-free or organic solvent-containing liquid reaction products into the ageing tank for stirred ageing; and performing hydrolysis by adding in deionized water to obtain hydrolyzed products, which, if containing no organic solvent, are p-nitrotoluene-2-sulfonic acid, else, performing extraction by adding in deionized water for dissolution in aqueous phase to obtain the p-nitrotoluene-2-sulfonic acid. The p-nitrotoluene-2-sulfonic acid continuous synthesis method has the advantages of being low in production cost, free from producing waste acid, high in safety performance and capable of achieving continuous production.

Aryl sulfonic acids and derivatives as FSH antagonists

This invention provides compounds of formula I having the structure wherein R1, Ar, Ar′, and Q are as defined in the specification, or a pharmaceutically acceptable salt thereof, which are useful as contraceptive agents.