Ethane-1,2-dithiol
Chemical compound C2H4(SH)2
From Wikipedia, the free encyclopedia
Ethane-1,2-dithiol, also known as EDT,[1] is a colorless liquid with the formula C2H4(SH)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.
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| Names | |
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| Preferred IUPAC name
Ethane-1,2-dithiol | |
| Other names
Dimercaptoethane 1,2-Ethanedithiol | |
| Identifiers | |
3D model (JSmol) |
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| ChemSpider | |
| ECHA InfoCard | 100.007.958 |
| EC Number |
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PubChem CID |
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| UNII | |
CompTox Dashboard (EPA) |
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| Properties | |
| C2H6S2 | |
| Molar mass | 94.19 g·mol−1 |
| Appearance | Colorless liquid |
| Density | 1.123 g/cm3 |
| Melting point | −41 °C (−42 °F; 232 K) |
| Boiling point | 146 °C (295 °F; 419 K) 46 mmHg |
| Slightly sol | |
| Solubility in other solvents | Good solubility in most organic solvents |
| Acidity (pKa) | ≈11 |
Refractive index (nD) |
1.5589 (D-line, 25 °C) |
| Hazards | |
| GHS labelling: | |
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| Danger | |
| H226, H301, H302, H310, H312, H319, H330 | |
| P210, P233, P240, P241, P242, P243, P260, P262, P264, P270, P271, P280, P284, P301+P310, P301+P312, P302+P350, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P310, P312, P320, P321, P330, P337+P313, P361, P363, P370+P378, P403+P233, P403+P235, P405, P501 | |
| NFPA 704 (fire diamond) | |
| Flash point | 50 °C (122 °F; 323 K) |
| Related compounds | |
Related thiols |
1,1-Ethanedithiol; Ethanethiol; 1,3-Propanedithiol; 1,2-Benzenedithiol; Thiophenol |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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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.[2]
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:
- 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).[3]
As a 1,2-dithiol, this compound reacts with aldehydes and ketones to give 1,3-dithiolanes, which can be useful intermediates.[4]
Other 1,2- and 1,3-dithiols give related 1,3-dithiolanes (five-membered) and 1,3-dithianes (six-membered rings). Diols such as ethylene glycol undergo analogous reactions to give 1,3-dioxolanes. 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.[citation needed]
Like 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:[5]
- Fe3(CO)12 + C2H4(SH)2 → Fe2(S2C2H4)(CO)6 + H2 + Fe(CO)5 + CO