Ethyl carbamate

  • Ethyl carbamate
  • Ethylurethane
  • Amidokohlensäureethylester

Colorless and odorless crystals

Fixed

0.99 g · cm -3 ( 21 ° C)

48.1 ° C

185 ° C

  • Good in water ( 350 g · l -1 at 11 ° C)
  • Soluble in ethanol, diethyl ether, chloroform, benzene, and glycerol

1.4144 (51 ° C)

Risk

-517.1 KJ / mol

Template: Infobox chemical / molecular formula search available

Urethane ( C3H7NO2 ) belongs to the chemical substance group of carbamates.

Generally

Urethane is not, as the name suggests, the monomer from polyurethane. Rather urethane has the same functional group, such as polyurethane, that the urethane group (- NH-CO -O-) which is present in high number in the PU. Urethane is formally formed by the reaction of isocyanuric acid (HN = C = O) with, for example, ethanol or other alcohols. The class of compounds of the urethanes therefore also refers to a class of materials containing the functional group mentioned above, not only the urethane, which carries an ethyl group ( ethyl carbamate ). Similarly, the reaction is carried out between the polyurethane di-, tri or polyisocyanates and polyhydric alcohols.

Production and representation

Urethane may be prepared by the action of ammonia on diethyl or common heating of urea nitrate with ethanol. Furthermore, it may be generated in the presence of catalytically active concentrated sulfuric acid by heating (100 ° C) equimolar amounts of urea and ethanol.

Occurrence

Urethane is a natural constituent of some foods, such as it is found in bread, wine and fermented beverages. Improper production of urethane can occur from stone fruit ( cherry brandy, plum brandy, plum eau de vie ) in higher concentrations, particularly in fires. It is known as a carcinogenic ( cancer-causing = ) connection. In Switzerland there is since 2003 an upper limit of 1 mg / l in spirits.

Use

Prior to 1970 it was used as a drug for the treatment of leukemia and varices. In the experimental animal research, it serves as a long-acting Injektionsnarkotikum.

Safety

Urethane damages the blood forming organs, the liver and the central nervous system and can cause cancer.

CAS registry number PubChem Dangerous Substances Directive (67/548/EEC) Chemical classification Fermentation Kirsch CRC Handbook of Chemistry and Physics
318083
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