Thiiran

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Structural formula
Structural formula of thiirane
General
Surname Thiiran
other names

Ethylene sulfide

Molecular formula C 2 H 4 S
Brief description

clear colorless liquid with an unpleasant odor

External identifiers / databases
CAS number 420-12-2
EC number 206-993-9
ECHA InfoCard 100.006.359
PubChem 9865
Wikidata Q220676
properties
Molar mass 60.12 g mol −1
Physical state

liquid

density

1.01 g cm −3

boiling point

55-56 ° C

Vapor pressure

287 h Pa (20 ° C)

Refractive index

1.495 (20 ° C)

safety instructions
GHS labeling of hazardous substances
02 - Highly / extremely flammable 05 - Corrosive 06 - Toxic or very toxic

danger

H and P phrases H: 225-301-318-331
P: 210-261-280-301 + 310-305 + 351 + 338-311
Toxicological data

178 mg kg −1 ( LD 50ratoral )

Thermodynamic properties
ΔH f 0

51.6 kJ / mol

As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

Thiirane , also called ethylene sulfide , is a sulfur-containing saturated three-membered heterocycle and thus the simplest representative of the thiirane group .

presentation

Thiirane is prepared by reacting ethylene oxide with thiourea in an aqueous medium with cooling. This creates thiirane and urea .

Depiction of Thiiran

Another possibility is the reaction of ethylene carbonate with potassium thiocyanate , which produces carbon dioxide and potassium cyanate in addition to thiirane .

properties

Ethylene sulfide is a liquid at room temperature compound having a boiling point at 55-56 ° C. The bond length between carbon and sulfur is 181.9  pm , between two carbons 149.2 pm. The bond angle at the sulfur atom is 65 ° 48 '.

Reactions

Thiirane reacts with nucleophiles with ring opening. It can therefore be used for the synthesis of terminal thiols . Amines or thiols, for example, can act as nucleophiles .

Ring opening of thiiran

It reacts with imines to form thiazolidines.

Addition of thiirane to 3,4-dihydroisoquinoline

However, the sulfur atom of thiirane can also serve as a nucleophile itself.

Individual evidence

  1. a b c d e f g h data sheet Ethylene sulfide from Sigma-Aldrich , accessed on April 24, 2011 ( PDF ).
  2. David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Standard Thermodynamic Properties of Chemical Substances, pp. 5-22.
  3. JF Olin, FB Dains in: J. Am. Chem. Soc. 1930, 52, 3322-3327. doi : 10.1021 / ja01371a047
  4. GL Cunningham, AW Boyd, RJ Myers, WD Gwinn in: J. Chem. Phys. 1951, 19, 6, 676-685; doi : 10.1063 / 1.1748331 .
  5. ^ MD Rozwadowska, A. Sulima in: Tetrahedron 2001 , 57 , 3499-3506. doi : 10.1016 / S0040-4020 (01) 00224-1