4189-44-0

Basic information

• Product Name: THIOUREA DIOXIDE
• Synonyms: Thiourea,S,S-dioxide(9CI);Urea,thio-,2,2-dioxide;THIO UREA 99% MIN.;THIOUREA DIOXIDE 99%MIN;Brn 1902754;Einecs 224-065-1
• CAS NO: 4189-44-0
• Molecular Formula: CH₄N₂O₂S
• Molecular Weight: 108.12
• EINECS: 217-157-8
• Mol File: 4189-44-0.mol
• Article Data: 4

Chemical Properties

• Melting Point: 126 °C
• Appearance: /
• Density: 2.254 g/cm³
• Refractive Index: 1.66
• Water Solubility: 30 g/L (20℃)
• CAS DataBase Reference: THIOUREA DIOXIDE(CAS DataBase Reference)
• NIST Chemistry Reference: THIOUREA DIOXIDE(4189-44-0)
• EPA Substance Registry System: THIOUREA DIOXIDE(4189-44-0)

Safety Data

• Hazard Codes: Xn:Harmful
• Statements: R22:; R36/37/38:
• Safety Statements: S24/25:
• Hazardous Substances Data: 4189-44-0(Hazardous Substances Data)

Usage

General Description

Thiourea dioxide, also known as formamidine sulfinic acid, is a powerful reducing agent used in a variety of industrial applications. It is commonly used as a bleaching agent in the textile and paper industries, as well as in the production of personal care products and pharmaceuticals. Thiourea dioxide is also used in the synthesis of dyes and as a component in metal-cleaning solutions. As a reducing agent, it has the ability to reduce disulfide and sulfide bonds, making it a valuable tool in various chemical processes. It is considered to be a safer and more environmentally friendly alternative to other reducing agents such as sodium hydrosulfite. However, its handling requires proper precautions due to its potential for skin and eye irritation.

InChI:InChI=1/CH4N2O2S/c2-1(3-4)6-5/h2-3H2

Synthetic route

thiourea (17356-08-0) → thiourea S,S-dioxide (4189-44-0)

Conditions	Yield
With dihydrogen peroxide; ammonium carbonate In water at 8℃; for 2.5h; pH=5 - 5.5;	80%
With dihydrogen peroxide In water at 10℃;	64%
With tert.-butylhydroperoxide In methanol; tert-butyl alcohol for 0.666667h; Ambient temperature;
With perchloric acid; potassium peroxomonosulfate In water at 30℃; Kinetics; Temperature;

thiourea S,S-dioxide (4189-44-0) → C-(3λ4-Dioxathiiran-3-ylidene)-methanediamine

Conditions	Yield
In [D3]acetonitrile at 45℃; Rate constant;

thiourea S,S-dioxide (4189-44-0) → thiourea (17356-08-0) + urea (57-13-6)

Conditions	Yield
In acetonitrile for 0.7h; Heating; Yield given;

thiourea S,S-dioxide (4189-44-0) → guanidine nitrate (113-00-8)

Conditions	Yield
With ammonia; oxygen In water at 24.85℃; Kinetics;

thiourea S,S-dioxide (4189-44-0) + isobutylamine (78-81-9) → isobutyl-guanidine (69724-02-3)

Conditions	Yield
With oxygen In water at 24.85℃; Kinetics;

thiourea S,S-dioxide (4189-44-0) + methylamine (74-89-5) → 1-methylguanidine (471-29-4)

Conditions	Yield
With oxygen In water at 24.85℃; Kinetics;

thiourea S,S-dioxide (4189-44-0) → urea (57-13-6)

Conditions	Yield
With oxygen In water at 24.84℃; pH=10.0; Kinetics; Further Variations:; pH-values; Reagents;

sodium hexachlororhodate(III) + thiourea S,S-dioxide (4189-44-0) → Rh(2+)*(NH2)2CSO2*SO3(2-)*H2O=Rh((NH2)2CSO2)SO3*H2O (12340-43-1)

Conditions	Yield
In hydrogenchloride in dilute HCl;

sodium hexachlororhodate(III) + thiourea S,S-dioxide (4189-44-0) → Rh(1+)*(NH2)2CSO2*HSO3(1-)*H2O=Rh((NH2)2CSO2)HSO3*H2O

Conditions	Yield
In hydrogenchloride in dilute HCl;

sodium hexachlororhodate(III) + thiourea S,S-dioxide (4189-44-0) → Rh(2+)*(NH2)2CSO2*2Cl(1-)*H2O=Rh((NH2)2CSO2)Cl2*H2O

Conditions	Yield
In hydrogenchloride in concd. HCl soln.;

thiourea S,S-dioxide (4189-44-0) → sulfoxylic acid (20196-46-7)

Conditions	Yield
With NaOH In water treatment of soln. thiourea dioxide with 0.5 M NaOH under inert atmosphere for 3 h at 298 K; adjusting pH by addn. buffer soln. with different acidity;

thiourea S,S-dioxide (4189-44-0) → carbon dioxide (124-38-9)

Conditions	Yield
With chlorine dioxide In aq. phosphate buffer; water-d2 at 11 - 25℃; for 1h; pH=2.5; Kinetics; Temperature; Inert atmosphere;

thiourea S,S-dioxide (4189-44-0) + silver nitrate → silver (II) carbonate

Conditions	Yield
Stage #1: thiourea S,S-dioxide With chlorine dioxide In aq. phosphate buffer; water-d2 at 11 - 25℃; for 1h; pH=2.5; Inert atmosphere; Stage #2: With sulfuric acid In aq. phosphate buffer; water-d2 Inert atmosphere; Heating; Stage #3: silver nitrate Inert atmosphere;

thiourea S,S-dioxide (4189-44-0) + hydrogen fluoride (7664-39-3) + germanium tetrafluoride (7783-58-6) → 2CH6N2O2S(2+)*4FH*F20Ge4(4-)

Conditions	Yield
at -196 - 20℃; Inert atmosphere;

thiourea S,S-dioxide (4189-44-0) → CH6N2O2S(2+)*2AsF6(1-)

Conditions	Yield
With hydrogen fluoride; arsenic pentafluoride at -196 - 20℃; Inert atmosphere;

thiourea S,S-dioxide (4189-44-0) → C(2)H6N2O2S(2+)*2AsF6(1-)

Conditions	Yield
With arsenic pentafluoride; hydrogen fluoride at -196 - 20℃; Inert atmosphere;

thiourea S,S-dioxide (4189-44-0) + hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) → CH6N2O2S(2+)*2F6Sb(1-)

Conditions	Yield
at -196 - 20℃; Inert atmosphere;

Upstream product

• 17356-08-0 thiourea 

Downstream Products

• 57-13-6 urea 
• 471-29-4 1-methylguanidine 
• 17356-08-0 thiourea 

Relevant articles and documents

Thiourea dioxide with TBHP: A fruitful and greener recipe for the catalytic oxidation of alcohols

Thiourea dioxide, owing to its hydrogen bonding ability, has been established as an exceptional, widely applicable organocatalyst. In the present paper, thiourea dioxide, an organocatalyst, in combination with t-butyl hydroperoxide (TBHP), a non-toxic and environmentally benign oxidant, serves to be a greener and more fruitful approach for the oxidation of alcohols to corresponding carbonyl compounds in excellent yields under mild reaction conditions. The Royal Society of Chemistry 2013.

Kinetics of the peroxomonosulfate oxidation of sulfur(-II) compounds: Thioacetamide, dithiooxamide and thiourea

Kinetics of relatively faster oxidation of thioacetamide (TA), dithiooxamide (DTO) and thiourea (TA) by peroxomonosulfate (PMS) has been studied spectrophotometrically under pseudo order condition by keeping oxidant in excess. Under these conditions, the sulfur(-II) compounds are oxidized to corresponding S-dioxides. The kinetics rate law for the oxidation of TA and TU both is eq. (A) and for the oxidation of DTO is eq. (B). (Equation Presented) The values of rate constant, k, at 30°C were 3.4 (DTO), 44 (TA) and 3.4 L mol-1 s-1 (TU) and those of protonation constants, K, were 3.2 (TU) and 19 (TA). A comparative rate analysis showed oxidation by PMS to be much faster than with H2O2.