Ethanimine is an organonitrogen compound classified as an

imine In organic chemistry, an imine ( or ) is a functional group or organic compound containing a carbon–nitrogen double bond (). The nitrogen atom can be attached to a hydrogen or an organic group (R). The carbon atom has two additional single bon ...

. It is formed by reacting acetaldehyde and ammonia, but rapidly polymerizes to acetaldehyde ammonia trimer. It has two

tautomer In chemistry, tautomers () are structural isomers (constitutional isomers) of chemical compounds that readily interconvert. The chemical reaction interconverting the two is called tautomerization. This conversion commonly results from the reloca ...

s: ethanimine, an imine, and ethenamine or aminoethylene, an

amine In chemistry, amines (, ) are organic compounds that contain carbon-nitrogen bonds. Amines are formed when one or more hydrogen atoms in ammonia are replaced by alkyl or aryl groups. The nitrogen atom in an amine possesses a lone pair of elec ...

. Ethanimine has two hydrogens on the carbon, while ethenamine has two on the nitrogen atom.

Occurrence

It is not well known terrestrially, but has been detected in abundance toward Sagittarius B2 (Sgr B2), a dense interstellar cloud between stars toward the

Galactic Center The Galactic Center is the barycenter of the Milky Way and a corresponding point on the rotational axis of the galaxy. Its central massive object is a supermassive black hole of about 4 million solar masses, which is called Sagittarius A*, a ...

of the

Milky Way The Milky Way or Milky Way Galaxy is the galaxy that includes the Solar System, with the name describing the #Appearance, galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars in other arms of the galax ...

. The distance between the Sgr B2 cloud and center of galaxy is 100 pc (1 pc = 3.26 ly). Ethanimine is mainly found in hot cores of ISM clouds; in case of Sgr B2, the region would be the Sgr B2 N and Sgr B2 M. Radio telescopes such as the

Green Bank Observatory The Green Bank Observatory (previously National Radio Astronomy Observatory, Green Bank) is an Observatory, astronomical observatory located in the United States National Radio Quiet Zone, National Radio Quiet Zone in Green Bank, West Virginia, G ...

Green Bank Telescope The Robert C. Byrd Green Bank Telescope (GBT) in Green Bank, West Virginia, US is the world's largest fully steerable radio telescope, surpassing the Effelsberg 100-m Radio Telescope in Germany. The Green Bank site was part of the National Rad ...

and those operated by the

National Radio Astronomy Observatory The National Radio Astronomy Observatory (NRAO) is a federally funded research and development center of the United States National Science Foundation operated under cooperative agreement by Associated Universities, Inc. for the purpose of radi ...

(measuring radio frequency light lambda ranging from 1–300 GHz) are able to detect organic molecules such as ethanimines because its internal

energy transition An energy transition (or energy system transformation) is a major structural change to energy supply and consumption in an energy system. Currently, a transition to sustainable energy is underway to limit climate change. Most of the sustainab ...

, more specifically the rotational transition is within the radio frequency of 14085 MHz = 140.8 GHz.

References

{{Molecules detected in outer space Imines Amines