Langbahn Team – Weltmeisterschaft

Ethane-1,2-dithiol

Ethane-1,2-dithiol
Ethane-1,2-dithiol
Ball-and-stick model of ethane-1,2-dithiol
Space-filling model of ethane-1,2-dithiol
Names
Preferred IUPAC name
Ethane-1,2-dithiol
Other names
Dimercaptoethane
1,2-Ethanedithiol
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.007.958 Edit this at Wikidata
EC Number
  • 208-752-3
RTECS number
  • KI3325000
UNII
  • InChI=1S/C2H6S2/c3-1-2-4/h3-4H,1-2H2 checkY
    Key: VYMPLPIFKRHAAC-UHFFFAOYSA-N checkY
  • InChI=1/C2H6S2/c3-1-2-4/h3-4H,1-2H2
    Key: VYMPLPIFKRHAAC-UHFFFAOYAA
  • SCCS
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
1.5589 (D-line, 25 °C)
Hazards
GHS labelling:
GHS02: FlammableGHS06: ToxicGHS07: Exclamation mark
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, P322, P330, P337+P313, P361, P363, P370+P378, P403+P233, P403+P235, P405, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g. diesel fuelInstability (yellow): no hazard codeSpecial hazards (white): no code
2
2
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).
checkY verify (what is checkY☒N ?)

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.

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]

Applications

As a 1,2-dithiol, this compound is widely used in organic chemistry because it reacts with aldehydes and ketones to give 1,3-dithiolanes, which are useful intermediates. [3]

C2H4(SH)2 + RR'CO → C2H4S2CRR' + H2O
Protecting a carbonyl group by converting it to a 1,3-dithiolane, using ethane-1,2-dithiol
Protecting a carbonyl group by converting it to a 1,3-dithiolane, using ethane-1,2-dithiol

Other 1,2- and 1,3-dithiols undergo this reaction to give related 1,3-dithiolanes and 1,3-dithianes (six-membered rings). Diols such as ethylene glycol undergo analogous reactions to 1,3-dioxolanes and 1,3-dioxanes. 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 is commonly used as a scavenger in peptide cleavage synthesis.

See also

References

  1. ^ Choi, H.; Aldrich, J.v. (1993-07-01). "Comparison of methods for the Fmoc solid-phase synthesis and cleavage of a peptide containing both tryptophan and arginine". International Journal of Peptide and Protein Research. 42 (1): 58–63. doi:10.1111/j.1399-3011.1993.tb00350.x. ISSN 1399-3011. PMID 8103765.
  2. ^ Speziale, A. J. (1963). "Ethanedithiol". Organic Syntheses; Collected Volumes, vol. 4, p. 401.
  3. ^ R. E. Conrow "Ethanedithiol" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. doi:10.1002/047084289X
Quelle: https://en.wikipedia.org/wiki/1,2-ethanedithiol