thionyl chloride









Thionyl chloride
Other namessulfurous oxychloride
sulfurous dichloride
sulfinyl chloride
sulfinyl dichloride
dichlorosulfoxide
Identifiers
CAS number7719-09-7
Properties
Molecular formulaSOCl2
Molar mass118.97 g/mol
Appearanceclear to yellow
odorous liquid
Density1.638 g ml−1, liquid
Melting point −104.5 °C
Boiling point 76 °C
Solubility in waterReactive
Viscosity0.6 cP at ? °C
Structure
Molecular shapepyramidal
Dipole moment1.4 D
Hazards
MSDSExternal MSDS
EU classificationCorrosive (C)
NFPA 704
0
4
2
W
R-phrasesR14, R20/22, R29, R35
S-phrasesS1/2, S26, S36/37/39, S45
Flash pointnon flammable
Related Compounds
Related compoundsSulfuryl chloride
Selenium oxydichloride
Except where noted otherwise, data are given for
materials in their standard state
(at 25 C, 100 kPa)



Thionyl chloride (or thionyl dichloride) is an inorganic compound with the formula SOCl2. SOCl2 is a reactive chemical reagent used in chlorination reactions. It is a colorless, distillable liquid at room temperature and pressure that decomposes above 140 °C. SOCl2 is sometimes confused with sulfuryl chloride, SO2Cl2, but the chemical properties of these S(IV) and S(VI) compounds differ significantly.

Properties and structure

The molecule SOCl2 is pyramidal, indicating the presence of a lone pair of electrons on the S(IV) center. In contrast, COCl2 is planar.

SOCl2 reacts with water to release hydrogen chloride and sulfur dioxide.
H2O + O=SCl2SO2 + 2 HCl


Because of its high reactivity toward water, SOCl2 would not be expected to occur in nature.

Industrial usage

Thionyl chloride is used inside lithium-thionyl chloride batteries as the positive active material with lithium as the negative active material. It is also used as a reagent for the production of other chemical compounds or materials.

In military usage, thionyl chloride is used in the "di-di" method of producing G-series nerve agents.

Use in organic chemistry

Thionyl chloride is widely used to convert carboxylic acids[1][2] and alcohols[3][4] to the corresponding acyl chlorides and alkyl chlorides respectively via an internal nucleophilic substitution. It is preferred over other reagents such as phosphorus pentachloride because the products of the thionyl chloride reactions, HCl and SO2 are gaseous, simplifying the purification of the product. Excess thionyl chloride may be removed by distillation.

RC(O)OH + O=SCl2RC(O)Cl + SO2 + HCl
R-OH + O=SCl2R-Cl + SO2 + HCl


Sulfonic acids react with thionyl chloride to produce sulfonyl chlorides.[5][6] Likewise, thionyl chloride will transform sulfinic acids into sulfinyl chlorides[7][8] and phosphonic acids into phosphoryl chlorides.

Miscellaneous reactions

Thionyl chloride will react with primary formamides to form isocyanides.[9]

Amides will react with thionyl chloride to form imidoyl chlorides. However, primary amides under heating with thionyl chloride will continue on to form nitriles.[10]

Synthesis of thionyl chloride

The major industrial synthesis involves the reaction of sulfur trioxide and sulfur dichloride:[11]

SO3 + SCl2SOCl2 + SO2.


Other methods include

SO2 + PCl5SOCl2 + POCl3;


SO2 + Cl2 + SCl2 → 2 SOCl2;


SO3 + Cl2 + 2 SCl2 → 3 SOCl2.


The first of the above three reactions also affords phosphorus oxychloride (or phosphoryl chloride), which resembles thionyl chloride in many of its reactions.

Safety and toxicity considerations

SOCl2 is toxic, corrosive, and lachrymatory. It is a skin and inhalation hazard, as well as being odorous. It can react explosively when exposed to high concentrations of nucleophiles such as phosphites.

Industrial production of thionyl chloride is controlled under the Chemical Weapons Convention, where it is listed in schedule 3.

References

1. ^ Allen, C. F. H.; Byers, Jr., J. R.; Humphlett, W. J. (1963). "Oleoyl chloride". Org. Synth.; Coll. Vol. 4: 739.  
2. ^ Rutenberg, M. W.; Horning, E. C. (1963). "1-Methyl-3-ethyloxindole". Org. Synth.; Coll. Vol. 4: 620.  
3. ^ Mondanaro, K. R.; Dailey, W. P. (2004). "3-Chloro-2-(chloromethyl)-1-propene". Org. Synth.; Coll. Vol. 10: 212.  
4. ^ Krakowiak, K. E.; Bradshaw, J. S. (1998). "4-Benzyl-10,19-diethyl-4,10,19-triaza-1,7,13,16-tetraoxacycloheneicosane". Org. Synth.; Coll. Vol. 9: 34.  
5. ^ Weinreb, S. M.; Chase, C. E.; Wipf, P.; Venkatraman, S. (2004). "2-Trimethylsilylethanesulfonyl chloride (SES-Cl)". Org. Synth.; Coll. Vol. 10: 707.  
6. ^ Hazen, G. G.; Bollinger, F. W.; Roberts, F. E.; Russ, W. K.; Seman, J. J.; Staskiewicz, S. (1998). "4-Dodecylbenzenesulfonyl azides". Org. Synth.; Coll. Vol. 9: 400.  
7. ^ Hulce, M.; Mallomo, J. P.; Frye, L. L.; Kogan, T. P.; Posner, G. H. (1990). "(S)-( + )-2-(p-toluenesulfinyl)-2-cyclopentenone: Precursor for enantioselective synthesis of 3-substituted cyclopentanones". Org. Synth.; Coll. Vol. 7: 495.  
8. ^ Kurzer, F. (1963). "p-Toluenesulfinyl chloride". Org. Synth.; Coll. Vol. 4: 937.  
9. ^ Niznik, G. E.; Morrison, III, W. H.; Walborsky, H. M. (1988). "1-d-Aldehydes from organometallic reagents: 2-methylbutanal-1-d". Org. Synth.; Coll. Vol. 6: 751.  
10. ^ Krynitsky, J. A.; Carhart, H. W. (1963). "2-Ethylhexanonitrile". Org. Synth.; Coll. Vol. 4: 436.  
11. ^ N. N. Greenwood, A. Earnshaw, Chemistry of the Elements, Pergamon Press, 1984.

External links

CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. They are also referred to as CAS numbers, CAS RNs or CAS #s.
..... Click the link for more information.
A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. A chemical formula is also a short way of showing how a chemical reaction occurs.
..... Click the link for more information.
Molar mass, symbol M,[1] is the mass of one mole of a substance (chemical element or chemical compound).[2] It is a physical property which is characteristic of each pure substance.
..... Click the link for more information.
In physics, density is mass m per unit volume V—how heavy something is compared to its size. A small, heavy object, such as a rock or a lump of lead, is denser than a lighter object of the same size or a larger object of the same weight, such as pieces of
..... Click the link for more information.
The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. Although the phrase would suggest a specific temperature and is commonly and incorrectly used as such in most textbooks and literature, most crystalline compounds
..... Click the link for more information.
boiling point of a liquid is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid.[1][2][3][4]
..... Click the link for more information.
Solubility is a physical property referring to the ability for a given substance, the solute, to dissolve in a solvent.[1] It is measured in terms of the maximum amount of solute dissolved in a solvent at equilibrium. The resulting solution is called a saturated solution.
..... Click the link for more information.
Water is a common chemical substance that is essential to all known forms of life.[1] In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor.
..... Click the link for more information.
Viscosity is a measure of the resistance of a fluid to deform under either shear stress or extensional stress. It is commonly perceived as "thickness", or resistance to flow.
..... Click the link for more information.
The poise (symbol P; IPA: /pwɑːz/) is the unit of dynamic viscosity in the centimetre gram second system of units. It is named after Jean Louis Marie Poiseuille.
..... Click the link for more information.
The debye (symbol: D) is a non-SI and non-CGS unit of electrical dipole moment. It is defined as 10-18 statcoulomb centimeter (or 10-20 esu m). In SI units, 1 D equals 3.33564*10-30 coulomb meter. It is named after the physicist Peter J.
..... Click the link for more information.
Council Directive 67/548/EEC of 27 June 1967 on the approximation of laws, regulations and administrative provisions relating to the classification, packaging and labelling of dangerous substances (as amended) is the main European Union law concerning chemical safety.
..... Click the link for more information.
NFPA 704 is a standard maintained by the U.S. National Fire Protection Association. It defines the colloquial "fire diamond" used by emergency personnel to quickly and easily identify the risks posed by nearby hazardous materials.
..... Click the link for more information.
R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous substances and preparations.
..... Click the link for more information.
S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. The list was consolidated and republished in Directive 2001/59/EC , where translations into other EU languages may be found.
..... Click the link for more information.
The flash point of a flammable liquid is the lowest temperature at which it can form an ignitable mixture in air. At this temperature the vapor may cease to burn when the source of ignition is removed.
..... Click the link for more information.
Sulfuryl chloride is SO2Cl2, a compound composed of sulfur, oxygen, and chlorine. At room temperature, it is a colorless liquid with a pungent odor.
..... Click the link for more information.
Selenium oxydichloride is the chemical compound SeOCl2, a close chemical relative of thionyl chloride, SOCl2. It is used occasionally as a polar solvent, which resembles DMSO as a donor solvent.

External links


..... Click the link for more information.
standard state of a material is its state at 1 bar (100 kilopascals exactly). This pressure was changed from 1 atm (101.325 kilopascals) by IUPAC in 1990.[1] The standard state of a material can be defined at any given temperature, most commonly 25 degrees Celsius,
..... Click the link for more information.
inorganic compounds are considered to be of mineral, not biological, origin. Complementarily, most organic compounds are traditionally viewed as being of biological origin.
..... Click the link for more information.
A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. A chemical formula is also a short way of showing how a chemical reaction occurs.
..... Click the link for more information.
6
(strongly acidic oxide)
Electronegativity 2.58 (Pauling scale)
Ionization energies
(more) 1st: 999.6 kJmol−1
2nd: 2252 kJmol−1
3rd: 3357 kJmol−1

Atomic radius 100 pm
Atomic radius (calc.
..... Click the link for more information.
2, −1
(neutral oxide)
Electronegativity 3.44 (Pauling scale)
Ionization energies
(more) 1st: 1313.9 kJmol−1
2nd: 3388.3 kJmol−1
3rd: 5300.5 kJmol−1

Atomic radius 60 pm
Atomic radius (calc.
..... Click the link for more information.
1, 3, 5, 7
(strongly acidic oxide)
Electronegativity 3.16 (Pauling scale)
Ionization energies
(more) 1st: 1251.2 kJmol−1
2nd: 2298 kJmol−1
3rd: 3822 kJmol−1

Atomic radius 100 pm
Atomic radius (calc.
..... Click the link for more information.
A reactant or reagent is a substance consumed during a chemical reaction.[1] Solvents and catalysts, although they are involved in the reaction, are usually not referred to as reactants.
..... Click the link for more information.
chemical reaction is a process that results in the interconversion of chemical substances.[1] The substance or substances initially involved in a chemical reaction are called reactants.
..... Click the link for more information.
Liquid is one of the four principal states of matter. A liquid is a fluid that can freely form a distinct surface at the boundaries of its bulk material.

Characteristics

A liquid's shape is determined by, not confined to, the container it fills.
..... Click the link for more information.
trillion fold).]]

Temperature is a physical property of a system that underlies the common notions of hot and cold; something that is hotter generally has the greater temperature. Temperature is one of the principal parameters of thermodynamics.
..... Click the link for more information.
Pressure (symbol: p) is the force per unit area applied on a surface in a direction perpendicular to that surface.

Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.
..... Click the link for more information.
Sulfuryl chloride is SO2Cl2, a compound composed of sulfur, oxygen, and chlorine. At room temperature, it is a colorless liquid with a pungent odor.
..... Click the link for more information.


This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.