DIMETHYLSULFOXIDE

Dimethylsulfoxide (DMSO)  - chemical substance with the formula - (CH3)2SO . Colorless, odorless liquid with a specific sweetish taste (insufficiently pure product has a characteristic smell of dimethyl sulfide ). An important bipolar aprotic solvent . It is widely used in various fields of chemistry , as well as as a medicine .
EC / List no.: 200-664-3
CAS no.: 67-68-5
Mol. formula: C2H6OS

Systematic name: dimethyl sulfoxide
Abbreviations:    DMSO, DMSO
Chem. formula:    C 2 H 6 OS
Physical properties
condition: liquid
Molar mass: 78.13 g / mol
Density: 1.1004 g / cm³
Dynamic viscosity: 0.001996 Pa s
Thermal properties
Temperature
 •  melting: 18.5 ° C
 •  boiling: 189 ° C
Chemical properties

Solubility
 • in water: unlimited
 • in ethanol:unlimited
 • in benzene: unlimited
 • in chloroform: unlimited
It was first synthesized in 1866 by the Russian chemist Alexander Zaitsev by oxidizing dimethyl sulfide with nitric acid . Over the next few decades, studies of the properties of this compound were not systematic. But it was actively used during the First World War in the hospitals of the Russian army in the treatment of injuries, fractures, wounds. Non-toxicity and non-cumulativeness in the body contributed well to this.

Interest in dimethyl sulfoxide in the West increased greatly after its unique dissolving ability was discovered in 1958 . In 1960, industrial production of dimethyl sulfoxide began. After that, the number of publications devoted to the study of the properties of DMSO increased dramatically.

Receiving 
The main method for obtaining DMSO is the oxidation of dimethyl sulfide . In industry, this process is carried out using nitric acid . DMSO is a by-product of the pulp and paper industry . The annual production of DMSO is measured in tens of thousands of tons.

Under laboratory conditions, potassium periodate in an organic solvent - water system can be used for mild and selective oxidation of dimethyl sulfide . However, laboratory methods for the preparation of DMSO are of no practical importance. This is due to the inconvenience of working with dimethyl sulfide, as well as the low commercial cost of the finished solvent.

Physical and chemical properties 
When mixed with water, noticeable heating occurs. Reacts with methyl iodide to form a sulfoxonium ion that can react with sodium hydride.

Application 
Application as a solvent 
DMSO is an important bipolar aprotic solvent. It is less toxic than other members of this group, such as dimethylformamide , dimethylacetamide , N-methyl-2-pyrrolidone, HMPTA. Due to its strong dissolving power, DMSO is often used as a solvent in chemical reactions involving inorganic salts, in particular in nucleophilic substitution reactions. The acidic properties of DMSO are weak, so it has become an important solvent in the chemistry of carbanions . In DMSO, the values ​​of non-aqueous pKa were measured for hundreds of organic compounds .

Due to its high boiling point, DMSO evaporates extremely slowly under normal atmospheric pressure. This makes it a very convenient solvent for heating reactions. At the same time, a rather high melting point limits its use in the low temperature range. After the reaction is carried out in a DMSO solution, the reaction mixtures are most often diluted with water to precipitate organic substances.

The deuterated form of DMSO, also known as DMSO-d6, is a convenient solvent for NMR spectroscopy due to its high dissolving power for a wide range of substances, the simplicity of its own spectrum, and its stability at high temperatures. The disadvantages of DMSO-d6 as a solvent for NMR spectroscopy are its high viscosity, which broadens the signals in the spectrum, and its high boiling point, which makes it difficult to recover the substance after analysis. Often DMSO-d6 is mixed with CDCl 3 or CD 2 Cl 2 to lower the viscosity and melting point.

DMSO finds more and more applications in the production of microelectronics .

DMSO is more effective and safer than gasoline or dichloromethane for removing paint stains .

Along with nitromethane, DMSO is also a tool that removes "super-glue" (hardened, but still fresh) and uncured polyurethane foam . Apparently, DMSO reacts only with external super-glue molecules, thus forming a barrier against the penetration of DMSO into the depths (This is the only way to explain the extremely long removal of super-glue, which is effective only with prolonged friction of the super-glue surface with a cloth moistened with DMSO. deeper penetration with abundant wetting with DMSO is not observed). It is recommended to work with rubber gloves (upon contact with DMSO, the skin on the fingers wrinkles as from prolonged contact with water).

The properties of DMSO dissolution of deposits from engine oil (sludge, varnishes, carbon deposits) in the internals of internal combustion engines when introduced into the oil and directly into the combustion chamber are noteworthy, and the flushing efficiency is such that in some cases the release of stuck piston rings and cleaning of oil drainage holes in the pistons is achieved , however, paint and varnish coatings of engine parts may dissolve, followed by the ingress of coating flakes into the oil lines.

Application in biology 
DMSO is used in PCR to inhibit the pairing of parental DNA molecules. Before the start of the reaction, it is added to the PCR mixture and interacts with complementary DNA regions , preventing their pairing and reducing the number of side processes  .

DMSO is also used as a cryoprotectant . It is added to the cell environment to prevent cell damage during freezing [4] . Approximately 10% DMSO can be used to safely cool cells and store them at liquid nitrogen temperature .

Application in medicine 
Main article: Dimexidum
It is used as a cryoprotectant in transplantology .

As a drug, purified dimethyl sulfoxide is used in the form of aqueous solutions (10-50%), as a local anti-inflammatory and analgesic agent, as well as in ointments - to increase the transdermal transfer of active substances, since it penetrates the skin and transfers other substances in a few seconds. The trade name of the drug is " Dimexid "

Cleaning 
In addition to the impurity of water, dimethyl sulfoxide can also contain dimethyl sulphide and sulphones . These impurities are disposed of by keeping the DMSO for 12 hours over barium oxide , sodium hydroxide , drierite, or fresh activated alumina . After that, the substance is distilled under reduced pressure (~ 2-4 mm Hg, boiling point about 50 ° C ) over granules of sodium hydroxide or barium oxide. A 4A molecular sieve is used to store the purified DMSO .

Security 
DMSO penetrates easily through intact skin, therefore solutions of toxic substances in DMSO can lead to poisoning when in contact with the skin (transdermal). May irritate the skin, especially with undiluted DMSO .

Dimethyl sulfoxide (abbreviated as DMSO) is Dimethyl sulfoxide, unitary enterprise.  500g.a highly polar and water-miscible organic liquid. It is essentially odorless and low in toxicity. Like all dipolar aprotic solvents, DMSO has a relatively high boiling point. 
    When mixed with water, noticeable heating occurs. Reacts with methyl iodide to form a sulfoxonium ion that can react with sodium hydride.

Synonyms: methanesulfinylmethane, methyl sulfoxide, dimethyl (oxide) sulfur, DMSO, Dimethyl sulfoxide, DMSO.

 Dimethyl Sulfoxide Applications
    Dimethyl sulfoxide is an excellent solvent for the preparation of active pharmaceutical ingredients and intermediates. Many specific reactions are most effective in DMSO, resulting in higher yields. The high polarity of DMSO allows it to dissolve many compounds that other solvents cannot. DMSO itself is a reagent in the class of environmentally friendly oxidation reactions.
    The powerful soluble properties of DMSO allow high asset loading, resulting in highly concentrated formulations in agrochemical formulations. DMSO is a safe and effective liquid formulation solvent for a number of active ingredients used in herbicides, insecticides, and fungicidal formulations, including propiconazole, pinoxaden, pyroxasulfone, mentaconazole, imazafar, imazamethabenzmethyl, tribupyrimphos, cyfopriluthrin, glyphophiloflophenol.

Dimethyl sulfoxide as a cryopreservative

   DMSO has the unusual ability to drastically reduce the freezing point of water while maintaining the viability of many types of cells and tissues. It is added to the cell environment to prevent cell damage during freezing. Approximately 10% DMSO can be used to safely cool cells and store them at liquid nitrogen temperature. This led to its use in cryopreservation media for stem cells obtained from human umbilical cord blood and reproductive tissue.

Dimethyl sulfoxide as solvent

     For the production and processing of polymers, DMSO is used to produce carbon fiber and some high performance polymers. Since it can dissolve Dimethyl sulfoxide substance characteristicsmany polymers, DMSO can be used to cast polymer films and fibers useful in the manufacture of purification membranes. DMSO can be used to clean up polymer residues (polyurethane / polyester) from parts manufacturing.

 It is less toxic than other members of this group, such as dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, HMPTA. Due to its strong dissolving power, DMSO is often used as a solvent in chemical reactions involving inorganic salts, in particular in nucleophilic substitution reactions. The acidic properties of DMSO are poorly expressed, so it has become an important solvent in the chemistry of carboanions. In D MSO, the values ​​of non-aqueous pKa were measured for hundreds of organic compounds

Due to its high boiling point, DMSO evaporates extremely slowly under normal atmospheric pressure. This makes it a very convenient solvent for heating reactions. At the same time, a rather high melting point limits its use in the low temperature range. After the reaction is carried out in a DMSO solution, the reaction mixtures are most often diluted with water to precipitate organic substances.

DMSO is more effective and safer than gasoline or dichloromethane for removing paint stains.

Along with nitromethane, DMSO is also a means of removing “super-glue” (hardened, but still fresh) and non-hardened polyurethane foam. Apparently, DMSO reacts only with external super-glue molecules, thus forming a barrier against the penetration of DMSO into the depths (This is the only way to explain the extremely long removal of the super-glue, which is effective only with prolonged friction of the super-glue surface with a cloth moistened with DMSO. deeper penetration with abundant wetting with DMSO is Cosmetic preparations with dimethyl sulfoxidenot observed).

Dimethyl sulfoxide in cosmetology.

It has unique dissolving properties, therefore it is now widely used in medicine and cosmetology. It easily and quickly (within a few seconds) penetrates through intact skin, transferring the active substances of medicinal or cosmetic products dissolved in it. Thus, it increases the effectiveness of ointments, creams, solutions - dramatically increasing the rate of penetration of active substances through the skin barrier. In addition, DMSO has anti-inflammatory and analgesic effects, and is harmful to many bacteria. DMSO in its pure form, when it gets on the skin, can cause irritation; therefore, for medicinal purposes, its aqueous solutions of various concentrations, usually from 10 to 70 percent, are most often used.

Dimethyl sulfoxide in crop production.

     The use of DMSO as a membrane penetrator creates a "sponge" effect. The plant absorbs nutrients through the leaf surface in the shortest possible time. DMSO is effective for the delivery of nutrients to the metabolic system of the plant and pulls substances in which it is dissolved through the membranes. Once in the cell, they are included in the physiological processes occurring in it, thereby increasing the activity of enzymes, activating the processes of respiration, the synthesis of proteins and carbohydrates, activating the processes of forming the area of ​​the leaf apparatus, increasing the productivity of photosynthesis. DMSO is a source of organic sulfur. The plant uses sulfur to constantly create new healthy cells and replace old ones with them. Without sulfur, the body will produce weak and dysfunctional cells. Sulfur maintains the permeability of cell membranes. DMSO ensures the entry of nutrients into the cell and the effective removal of toxins and waste products. DMSO is safe - it does not accumulate in the plant (no traces of DMSO were found in the plants after foliar dressing).Dimexide is actively used in the fields as a part of fertilizers

Application phases

- in autumn 2 ... 3 weeks before the onset of frost:

winter wheat, triticale, rye, winter barley - in the tillering phase;
winter rape - in the phase of 4 ... 6 true leaves;
- in spring:

winter and spring wheat, triticale, rye, barley - in the tillering phase;
corn - in the phase of 5 ... 7 leaves;
sunflower - in the phase of 6 ... 8 leaves;
rapeseed - in the phase of 6 ... 8 true leaves.
    Doses for foliar dressing are from 0.006 kg to 0.04 per 1 liter of solution. (concentration depends on water quality) Costs per hectare from 149 rubles Correct and timely use of the tank mixture guarantees an increase in frost and drought resistance of plants by 25% -30%. Retains a prolonged action for the entire growing season. The use of DMSO makes it possible to reduce the dosage and save the funds of the enterprise of plant protection products to 1/2 of the minimum recommended by the manufacturer of plant nutrients by 30%.

The use of dimethyl sulfoxide in the leather industryDimethyl sulfoxide in leather formulations

   In experiments with leather tissue, it was found that D MSO greatly enhances the transmission of water through it. For example, the rate of water penetration through the stratum corneum when using dimethyl sulfoxide in solution increases 125 times. It is obvious that dimexide overcomes the skin barrier through the follicles and intercellular spaces.
In addition to its great "transport capacity", dimethyl sulfoxide can form complexes with metal ions with a variable valence, for example, chromium ions, and bind with collagen peptide groups. The described properties of dimethyl sulfoxide make it possible to use it in the process of dressing hides at the stage of processing the skin before the start of chrome tanning and directly in the tanning of the leather itself.It was found during the study that the use of dimexide and its homologon during dressing leads to an improvement in the quality of leather, and a decrease in dressing time. and reducing the chromium oxide content in the spent tanning solution. Leathers, chrome tanned with the use of dimethyl sulfoxide (Dimexide), have better physical, mechanical and hygienic properties, and the content of chromium oxide in the leather increases ..

Application of dimethyl sulfoxide in biology

    DMSO is used in polymerase chain reaction (PCR) to inhibit the pairing of parental DNA molecules. It is added to the PCR mixture before the start of the reaction, where it interacts with complementary DNA regions, preventing their pairing and reducing the number of side processes.

The use of dimethyl sulfoxide in medicine

    As a drug, purified dimethyl sulfoxide is used in the form of aqueous solutions (10-50%), as a local anti-inflammatory and analgesic agent, as well as in ointments to increase the transdermal transfer of active substances, since it Dimethyl sulfoxide_chemistry.jpgpenetrates the skin and transfers other substances in a few seconds. The trade name of the drug is "Dimexid".

Dimethyl sulfoxide
EC Inventory, Pre-Registration process, Other, Cosmetic Products Regulation, Annex II - Prohibited Substances
dimethyl sulphoxide
FCM and Articles Regulation, Annex I - Authorised Substances
CAS names
Methane, 1,1'-sulfinylbis-
Other
IUPAC names
Dimethyl sulphoxide, anhydrous
C&L Inventory
Dimethylsulfoxid
Registration dossier
Dimethylsulfoxide
C&L Inventory
DMSO, Methyl Sulfoxide
Registration dossier
methanesulfinylmethane
C&L Inventory, Other
Methylsulfinidemethane
C&L Inventory
methylsulfinylmethan
C&L Inventory
methylsulfinylmethane