View source for Ethane-1,2-dithiol

{{Short description|Chemical compound C2H4(SH)2}}
{{chembox
|Watchedfields = changed
|verifiedrevid = 477204496
|Name = Ethane-1,2-dithiol
|ImageFile = Ethanedithiol.png
|ImageSize = 150px
|ImageName = Ethane-1,2-dithiol
|ImageFile1 = Ethane-1,2-dithiol-3D-balls.png
|ImageSize1 = 150px
|ImageName1 = Ball-and-stick model of ethane-1,2-dithiol
|ImageFile2 = Ethane-1,2-dithiol-3D-vdW.png
|ImageSize2 = 150px
|ImageName2 = Space-filling model of ethane-1,2-dithiol
|PIN = Ethane-1,2-dithiol
|OtherNames = Dimercaptoethane<br />1,2-Ethanedithiol
|Section1={{Chembox Identifiers
|UNII_Ref = {{fdacite|correct|FDA}}
|UNII = 92T634FLAR
|SMILES = SCCS
|ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
|ChemSpiderID = 13865015
|PubChem = 10902
|EC_number = 208-752-3
|InChI = 1/C2H6S2/c3-1-2-4/h3-4H,1-2H2
|InChIKey = VYMPLPIFKRHAAC-UHFFFAOYAA
|StdInChI_Ref = {{stdinchicite|correct|chemspider}}
|StdInChI = 1S/C2H6S2/c3-1-2-4/h3-4H,1-2H2
|StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
|StdInChIKey = VYMPLPIFKRHAAC-UHFFFAOYSA-N
|CASNo_Ref = {{cascite|correct|CAS}}
|CASNo = 540-63-6
|RTECS = KI3325000
}}
|Section2={{Chembox Properties
| C=2 | H=6 | S=2
|Appearance = Colorless liquid
|Density = 1.123 g/cm{{sup|3}}
|Solubility = Slightly sol 
|Solvent = other solvents
|SolubleOther = Good solubility in<br />most organic solvents
|MeltingPtC = -41
|BoilingPtC = 146
|BoilingPt_notes = 46 mmHg
|pKa = ≈11
|RefractIndex = 1.5589 (D-line, 25 °C) 
}}
|Section7={{Chembox Hazards
|NFPA-H = 2 
|NFPA-F = 2 
|FlashPtC = 50
|GHSPictograms = {{GHS02}}{{GHS06}}{{GHS07}}
|GHSSignalWord = Danger
|HPhrases = {{H-phrases|226|301|302|310|312|319|330}}
|PPhrases = {{P-phrases|210|233|240|241|242|243|260|262|264|270|271|280|284|301+310|301+312|302+350|302+352|303+361+353|304+340|305+351+338|310|312|320|321|322|330|337+313|361|363|370+378|403+233|403+235|405|501}}
}}
|Section8={{Chembox Related
|OtherFunction_label = [[thiol]]s
|OtherFunction = [[1,1-Ethanedithiol]]; [[Ethanethiol]]; [[1,3-Propanedithiol]]; [[1,2-Benzenedithiol]]; [[Thiophenol]]
}}
}}

'''Ethane-1,2-dithiol''', also known as '''EDT''',<ref>{{Cite journal|last=Choi|first=H.|last2=Aldrich|first2=J.v.|date=1993-07-01|title=Comparison of methods for the Fmoc solid-phase synthesis and cleavage of a peptide containing both tryptophan and arginine|journal=International Journal of Peptide and Protein Research|language=en|volume=42|issue=1|pages=58–63|doi=10.1111/j.1399-3011.1993.tb00350.x|pmid=8103765|issn=1399-3011}}</ref> is a colorless [[liquid]] with the [[Chemical formula|formula]] [[Carbon|C]]{{sub|2}}[[Hydrogen|H]]{{sub|4}}([[Thiol|SH]]){{sub|2}}. It has a very characteristic odor which is compared by many people to rotten [[cabbage]]. It is a common building block in [[organic synthesis]] and an excellent [[ligand]] for metal ions.

==Preparation==
Ethane-1,2-dithiol is  made commercially by the reaction of [[1,2-dichloroethane]] with aqueous [[sodium bisulfide]]. In the laboratory, it can also be prepared by the action of [[1,2-dibromoethane]] on [[thiourea]] followed by [[hydrolysis]].<ref>{{OrgSynth | author = Speziale, A. J. | title = Ethanedithiol | collvol = 4 | collvolpages = 401 | year = 1963 | prep = cv4p0401}}</ref>

==Reactions==
1,2-Ethanedithiol is a weak acid, typical of alkyl thiols.  In the presence of base and an alkylating agent, 1,2-ethanedithiol converts to thioethers:
:{{chem2|HS(CH2)2SH  +  2 NR3  +  2 R'I  ->  R'S(CH2)2SR'  +  2 [R3NH]I}}

Oxidation of 1,2-ethanedithiol gives a series of oligomers, including the cyclic bis([[disulfide]]).<ref>{{cite journal |doi=10.1016/S0040-4039(00)87577-2 |title=Preparation, Properties and Crystal Structure of 1,2,5,6-Tetrathiacyclooctane |date=1982 |last1=Goodrow |first1=Marvin H. |last2=Olmstead |first2=Marilyn M. |last3=Musker |first3=W.Kenneth |journal=Tetrahedron Letters |volume=23 |issue=32 |pages=3231–3234 }}</ref>

As a 1,2-[[dithiol]], this compound reacts with [[aldehyde]]s and [[ketone]]s to give 1,3-[[dithiolane]]s, which can be useful intermediates.<ref>R. E. Conrow "Ethanedithiol" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. {{doi|10.1002/047084289X}}</ref>
[[File:Carbonyl-protection-with-ethanedithiol-2D.png|center|400px|Protecting a carbonyl group by converting it to a 1,3-dithiolane, using ethane-1,2-dithiol]]

Other 1,2- and 1,3-dithiols give related 1,3-dithiolanes (five-membered) and 1,3-dithianes (six-membered rings). [[Diol]]s such as [[ethylene glycol]] undergo analogous reactions to give 1,3-[[dioxolane]]s.  One distinguishing feature of the dithiolanes and dithianes derived from aldehydes is that the methyne group can be deprotonated and the resulting carbanion alkylated.

1,2-Ethanedithiol has been used as a scavenger in peptide cleavage synthesis.{{cn|date=February 2025}}

Like [[1,3-Propanedithiol|1,3-propanedithiol]], 1,2-ethanedithiol readily forms [[metal thiolate complexes]].  Illustrative is the synthesis of the derivative diiron ethanedithiolate hexacarbonyl upon reaction with [[triiron dodecacarbonyl]]:<ref>{{cite journal |doi=10.1016/j.ccr.2023.215174 |title=An Unexpected leading role for &#91;Fe<sub>2</sub>(CO)<sub>6</sub>(μ-PDT)&#93; in our Understanding of &#91;FeFe&#93;-H<sub>2</sub>ases and the Search for Clean Hydrogen Production |date=2023 |last1=Hogarth |first1=Graeme |journal=Coordination Chemistry Reviews |volume=490 |doi-access=free }}</ref>
:Fe<sub>3</sub>(CO)<sub>12</sub> +  C<sub>2</sub>H<sub>4</sub>(SH)<sub>2</sub>  →   Fe<sub>2</sub>(S<sub>2</sub>C<sub>2</sub>H<sub>4</sub>)(CO)<sub>6</sub>  +  H<sub>2</sub>  +  Fe(CO)<sub>5</sub>  +  CO

== See also ==
*[[Ethane-1,1-dithiol]]

==References==
<references />

{{DEFAULTSORT:Ethanedithiol, 1, 2-}}
[[Category:Thiols]]
[[Category:Reagents for organic chemistry]]
[[Category:Chelating agents]]
[[Category:Foul-smelling chemicals]]
[[Category:1,2-Ethanediyl compounds]]