Dimethylsulfoxide

Dimethyl sulfoxide

A sample of dimethyl sulfoxide
Names
IUPAC name Dimethyl sulfoxide
Systematic IUPAC name Methanesulfinylmethane (substitutive) Dimethyl(oxido)sulfur (additive)
Other names Methylsulfinylmethane Methyl sulfoxide
Identifiers
CAS Number	67-68-5 Y
3D model (Jmol)	Interactive image Interactive image
Abbreviations	DMSO, Me2SO
Beilstein Reference	506008
ChEBI	CHEBI:28262 Y
ChemSpider	659 Y
DrugBank	DB01093 Y
ECHA InfoCard	100.000.604
EC Number	200-664-3
Gmelin Reference	1556
KEGG	D01043 Y
MeSH	Dimethyl+sulfoxide
PubChem CID	679
RTECS number	PV6210000
UNII	YOW8V9698H Y
InChI InChI=1S/C2H6OS/c1-4(2)3/h1-2H3 Y Key: IAZDPXIOMUYVGZ-UHFFFAOYSA-N Y InChI=1/C2H6OS/c1-4(2)3/h1-2H3 Key: IAZDPXIOMUYVGZ-UHFFFAOYAR
SMILES CS(=O)C CS(C)=O
Properties
Chemical formula	C2H6OS
Molar mass	78.13 g·mol−1
Appearance	Colourless liquid
Density	1.1004 g cm−3
Melting point	19 °C (66 °F; 292 K)
Boiling point	189 °C (372 °F; 462 K)
Solubility in water	Miscible
Solubility in diethyl ether	very soluble
Acidity (pKa)	35
Refractive index (nD)	1.479 εr = 48
Viscosity	1.996 cP at 20 °C
Structure
Point group	Cs
Molecular shape	trigonal pyramidal
Dipole moment	3.96 D
Pharmacology
ATC code	G04BX13 (WHO) M02AX03 (WHO)
Hazards
Main hazards	Irritant and flammable
Safety data sheet	See: data page Oxford MSDS
R-phrases	R36/37/38
S-phrases	S26, S37/39
NFPA 704	2 1 0
Flash point	89 °C
Related compounds
Related sulfoxides	diethyl sulfoxide
Related compounds	sodium methylsulfinylmethylide, dimethyl sulfide, dimethyl sulfone, acetone
Supplementary data page
Structure and properties	Refractive index (n), Dielectric constant (εr), etc.
Thermodynamic data	Phase behaviour solid–liquid–gas
Spectral data	UV, IR, NMR, MS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Dimethyl sulfoxide (DMSO) is an organosulfur compound with the formula (CH₃)₂SO. This colorless liquid is an important polar aprotic solvent that dissolves both polar and nonpolar compounds and is miscible in a wide range of organic solvents as well as water. It has a relatively high melting point. DMSO has the unusual property that many individuals perceive a garlic-like taste in the mouth after contact with the skin.

In terms of chemical structure, the molecule has idealized C_s symmetry. It has a trigonal pyramidal molecular geometry consistent with other three-coordinate S(IV) compounds, with a nonbonded electron pair on the approximately tetrahedral sulfur atom.

It was first synthesized in 1866 by the Russian scientist Alexander Zaytsev, who reported his findings in 1867. Dimethyl sulfoxide is produced industrially from dimethyl sulfide, a by-product of the Kraft process, by oxidation with oxygen or nitrogen dioxide.

The sulfur center in DMSO is nucleophilic toward soft electrophiles and the oxygen is nucleophilic toward hard electrophiles. With methyl iodide it forms trimethylsulfoxonium iodide, [(CH₃)₃SO]I: