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The '''Reed reaction''' is a [[chemical reaction]] that utilizes [[photochemistry|light]] to [[redox|oxidize]] [[hydrocarbon]]s to [[sulfonyl chloride]]s. The reaction performs via the [[free radicals]]. First, the light makes a molecule of [[chlorine]] dissociate [[homolysis (chemistry)|homolytically]], then a chlorine atom produced attacks the hydrocarbon chain to form [[hydrogen chloride]] what results in the formation of [[alkyl]] free radical. Then [[Sulfur dioxide|SO<sub>2</sub>]] as an [[electron donor]] bonds to the [[reaction center]], forming an [[sulfonyl]] radical. Finally, the least one attacks another chlorine molecule to produce a sulfonyl chloride and a new chlorine atom which continues the reaction chain.
The '''Reed reaction''' is a [[chemical reaction]] that utilizes [[photochemistry|light]] to [[redox|oxidize]] [[hydrocarbon]]s to alkyl[[sulfonyl chloride]]s. This reaction is employed in modifying polyethylene to give [[chlorosulfonated polyethylene]] (CSPE), which is noted for its toughness.<ref name=Ullmann>{{Ullmann|doi=10.1002/14356007.o23_o05|isbn=978-3527306732|title=Rubber, 8. Synthesis by Polymer Modification|year=2011|last1=Happ|first1=Michael|last2=Duffy|first2=John|last3=Wilson|first3=G. J.|last4=Pask|first4=Stephen D.|last5=Buding|first5=Hartmuth|last6=Ostrowicki|first6=Andreas}}</ref>

{{also|Chain reaction}}


==Commercial implementations==
[[Image:Reed Reaction Scheme.png|center|350px|The Reed reaction]]
[[Image:Reed Reaction Scheme.png|center|350px|The Reed reaction]]

Polyethylene is treated with a mixture of chlorine and sulfur dioxide under UV-radiation. Vinylsulfonic acid can also be prepared beginning with the '''sulfochlorination''' of [[chloroethane]]. [[Dehydrohalogenation]] of the product gives vinylsulfonyl chloride, which subsequently is hydrolyzed to give [[vinylsulfonic acid]]:
::{{chem2|ClCH2CH3 + SO2 + Cl2 -> ClCH2CH2SO2Cl + HCl}}

::{{chem2|ClCH2CH2SO2Cl ->H2C}}={{chem2|CHSO2Cl + HCl}}

::{{chem2|CH2}}={{chem2|CHSO2Cl + H2O -> H2C}}={{chem2|CHSO3H + HCl}}

==Mechanism==
The reaction occurs via a [[free radical]] mechanism. UV-light initiates [[Homolysis (chemistry)|homolysis]] of [[chlorine]], producing a pair of chlorine atoms:


Chain initiation:
Chain initiation:
::::<math>Cl_2 \xrightarrow{h\nu} 2Cl\cdot </math>
::::<chem>Cl2 ->[h\nu] 2Cl. </chem>


Thereafter a chlorine atom attacks the hydrocarbon chain, freeing hydrogen to form [[hydrogen chloride]] and an [[alkyl]] free radical. The resulting radical then captures [[Sulfur dioxide|SO<sub>2</sub>]]. The resulting [[sulfonyl]] [[Radical (chemistry)|radical]] attacks another chlorine molecule to produce the desired sulfonyl chloride and a new chlorine atom, which continues the reaction chain.
Chain propagation steps:
Chain propagation steps:
::::<math>R-H + \cdot Cl \longrightarrow R \cdot + HCl</math>
::::<chem>{R-H} + .Cl -> {R.} + HCl</chem>
::::<math>R\cdot + :\!SO_2 \longrightarrow R- \dot{S} O_2</math>
::::<chem>{R.} + {:}SO2 -> R-\dot{S}O2</chem>
::::<math>R- \dot{S} O_2 + Cl_2 \longrightarrow R-SO_2-Cl + Cl \cdot </math>
::::<chem>{R-\dot{S}O2} + Cl2 -> {R-SO2-Cl} + Cl. </chem>


==See also==
The resulting sulfonyl chlorides are widely used in the [[detergent]] industry as a [[raw material]].
* [[Chain reaction]]


==Historical readings==
Under particular circumstances (40–80 °C) only [[halogenation|chlorination]] of alkane may take place.
* Reed, C. F. {{US patent|2046090}}; {{US patent|2174110}}; {{US patent|2174492}}.
::::<math>R-H + SO_2Cl_2 \rightarrow\ R-Cl + SO_2 + HCl</math>
* {{cite journal|doi=10.1002/cber.19420750105|title=Zur Kenntnis der Produkte der gemeinsamen Einwirkung von Schwefeldioxyd und Chlor auf aliphatische Kohlenwasserstoffe im ultravioletten Licht, I. Mitteil.: Die Produkte der gemeinsamen Einwirkung von Schwefeldioxyd und Chlor auf Propan in Tetrachlorkohlen|year=1942|last1=Asinger|first1=Friedrich|last2=Schmidt|first2=Walter|last3=Ebeneder|first3=Franz|journal=Berichte der Deutschen Chemischen Gesellschaft (A and B Series)|volume=75|pages=34–41}}
* {{cite journal|doi=10.1002/cber.19420750106|title=Zur Kenntnis der Produkte der gemeinsamen Einwirkung von Schwefeldioxyd und Chlor auf aliphatische Kohlenwasserstoffe im ultravioletten Licht, II. Mitteil.: Die Produkte der gemeinsamen Einwirkung von Schwefeldioxyd und Chlor auf n-Butan in Tetrachlorkohl|year=1942|last1=Asinger|first1=Friedrich|last2=Ebeneder|first2=Franz|last3=Böck|first3=Erich|journal=Berichte der Deutschen Chemischen Gesellschaft (A and B Series)|volume=75|pages=42–48}}
* {{Cite journal |last1=Asinger |first1=Friedrich |last2=Ebeneder |first2=Franz |date=1942 |title=Zur Kenntnis der Produkte der gemeinsamen Einwirkung von Schwefeldioxyd und Chlor auf aliphatische Kohlenwasserstoffe im ultravioletten Licht, III. Mitteilung† : Über die Sulfochlorierung von Isobutan und die Isomerenbildung bei der Sulfochlorierung und Chlorierung gasförmiger Kohlenwasserstoffe |url=https://onlinelibrary.wiley.com/doi/abs/10.1002/cber.19420750408 |journal=Berichte der Deutschen Chemischen Gesellschaft (A and B Series) |volume=75 |issue=4 |pages=344–349 |doi=10.1002/cber.19420750408 |issn=1099-0682 |accessdate=2023-02-22}}
* {{cite journal|author1=Helberger, J. H. |title=Zur Kenntnis organischer Sulfonsäuren. II. Mitt.: Die Sulfochlorierung des 1-Chlorbutans und anderer Halogenalkyle; Synthese von Sultonen und eines Sultams |author2=Manecka, G. |author3=Fischer, H. M. |journal=Justus Liebigs Annalen der Chemie|year=1949|volume=562|pages=23–35 |doi=10.1002/jlac.19495620104}}


==References==
==References==
<references />
* C. F. Reed, {{US patent|2046090}}; {{US patent|2174110}}; {{US patent|2174492}}.
{{Organic reactions}}
* Asinger, F. ''et al.'' ''[[Chemische Berichte|Ber.]]'' '''1942''', ''75'', 34.
* Asinger, F. ''et al.'' ''[[Chemische Berichte|Ber.]]'' '''1942''', ''75'', 42.
* Asinger, F. ''et al.'' ''[[Chemische Berichte|Ber.]]'' '''1942''', ''75'', 344.
* Helberger, J. H.; Manecka, G.; Fischer, H. M. ''Ann.'' '''1949''', ''562'', 23.

[[Category:Substitution reactions]]
[[Category:Substitution reactions]]
[[Category:Carbon-heteroatom bond forming reactions]]
[[Category:Carbon-heteroatom bond forming reactions]]
[[Category:Name reactions]]
[[Category:Name reactions]]

{{reaction-stub}}

Latest revision as of 13:34, 23 December 2024

The Reed reaction is a chemical reaction that utilizes light to oxidize hydrocarbons to alkylsulfonyl chlorides. This reaction is employed in modifying polyethylene to give chlorosulfonated polyethylene (CSPE), which is noted for its toughness.[1]

Commercial implementations

[edit]
The Reed reaction
The Reed reaction

Polyethylene is treated with a mixture of chlorine and sulfur dioxide under UV-radiation. Vinylsulfonic acid can also be prepared beginning with the sulfochlorination of chloroethane. Dehydrohalogenation of the product gives vinylsulfonyl chloride, which subsequently is hydrolyzed to give vinylsulfonic acid:

ClCH2CH3 + SO2 + Cl2 → ClCH2CH2SO2Cl + HCl
ClCH2CH2SO2Cl → H2C=CHSO2Cl + HCl
CH2=CHSO2Cl + H2O → H2C=CHSO3H + HCl

Mechanism

[edit]

The reaction occurs via a free radical mechanism. UV-light initiates homolysis of chlorine, producing a pair of chlorine atoms:

Chain initiation:

Thereafter a chlorine atom attacks the hydrocarbon chain, freeing hydrogen to form hydrogen chloride and an alkyl free radical. The resulting radical then captures SO2. The resulting sulfonyl radical attacks another chlorine molecule to produce the desired sulfonyl chloride and a new chlorine atom, which continues the reaction chain. Chain propagation steps:

See also

[edit]

Historical readings

[edit]
  • Reed, C. F. U.S. patent 2,046,090; U.S. patent 2,174,110; U.S. patent 2,174,492.
  • Asinger, Friedrich; Schmidt, Walter; Ebeneder, Franz (1942). "Zur Kenntnis der Produkte der gemeinsamen Einwirkung von Schwefeldioxyd und Chlor auf aliphatische Kohlenwasserstoffe im ultravioletten Licht, I. Mitteil.: Die Produkte der gemeinsamen Einwirkung von Schwefeldioxyd und Chlor auf Propan in Tetrachlorkohlen". Berichte der Deutschen Chemischen Gesellschaft (A and B Series). 75: 34–41. doi:10.1002/cber.19420750105.
  • Asinger, Friedrich; Ebeneder, Franz; Böck, Erich (1942). "Zur Kenntnis der Produkte der gemeinsamen Einwirkung von Schwefeldioxyd und Chlor auf aliphatische Kohlenwasserstoffe im ultravioletten Licht, II. Mitteil.: Die Produkte der gemeinsamen Einwirkung von Schwefeldioxyd und Chlor auf n-Butan in Tetrachlorkohl". Berichte der Deutschen Chemischen Gesellschaft (A and B Series). 75: 42–48. doi:10.1002/cber.19420750106.
  • Asinger, Friedrich; Ebeneder, Franz (1942). "Zur Kenntnis der Produkte der gemeinsamen Einwirkung von Schwefeldioxyd und Chlor auf aliphatische Kohlenwasserstoffe im ultravioletten Licht, III. Mitteilung† : Über die Sulfochlorierung von Isobutan und die Isomerenbildung bei der Sulfochlorierung und Chlorierung gasförmiger Kohlenwasserstoffe". Berichte der Deutschen Chemischen Gesellschaft (A and B Series). 75 (4): 344–349. doi:10.1002/cber.19420750408. ISSN 1099-0682. Retrieved 2023-02-22.
  • Helberger, J. H.; Manecka, G.; Fischer, H. M. (1949). "Zur Kenntnis organischer Sulfonsäuren. II. Mitt.: Die Sulfochlorierung des 1-Chlorbutans und anderer Halogenalkyle; Synthese von Sultonen und eines Sultams". Justus Liebigs Annalen der Chemie. 562: 23–35. doi:10.1002/jlac.19495620104.

References

[edit]
  1. ^ Happ, Michael; Duffy, John; Wilson, G. J.; Pask, Stephen D.; Buding, Hartmuth; Ostrowicki, Andreas (2011). "Rubber, 8. Synthesis by Polymer Modification". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.o23_o05. ISBN 978-3527306732.