1-Aminoethanol is an organic compound with the formula CHCH(NH)OH. It is classified as an alkanolamine. Specifically, it is a structural isomer of 2-aminoethanol (ethanolamine). These two compounds differ in the position of the amino group. Since the central carbon atom in 1-aminoethanol has four different substituents, the compound has two stereoisomers. Unlike 2-aminoethanol, which is of considerable importance in commerce, 1-aminoethanol is not encountered as a pure material and is mainly of theoretical interest.
1-Aminoethanol exists in a solution of acetaldehyde and aqueous ammonia.
1-Aminoethanol is suggested as intermediate in Strecker reaction of alanine synthesis.
1-Aminoethanol was first prepared in 1833 by the German chemist Johann Wolfgang Döbereiner; its empirical formula was first determined by the German chemist Justus von Liebig in 1835.Liebig, Justus (1835) "Ueber die Producte der Oxydation des Alkohols" (On the products of oxidation of alcohol [i.e., ethanol]), Annalen der Chemie, 14 : 133–167. In 1821, Döbereiner had prepared what he called Saüerstoffäther (literally: ether oxide), which, as Liebig later showed, contained acetaldehyde. On p. 134, Liebig states that Döbereiner first produced 1-amino-ethanol by perfusing acetaldehyde (Saüerstoffäther or Aldehyd, as Liebig called it) with ammonia gas (Ammoniak) : "Der berühmte Entdecker des Acetals theilte mir damals gleichzeitig mit, dass sein Saüerstoffäther mit Ammoniakgas eine weisse krystallinische Verbingdung bilde; ... " (The famous discoverer of acetal [viz, Döbereiner] simultaneously communicated to me at that time that his ether oxide forms a white crystalline compound with ammonia gas; ... ) On p. 146, Liebig presented his empirical formula for 1-aminoethanol: CHNO. If the subscripts are divided by 2, the resulting formula is correct. The structure of 1-aminoethanol remained unproven until 1877, when the German-Italian chemist Robert Schiff showed that the structure was CHCH(OH)NH.Although it had long been assumed that the structure of 1-aminoethanol was CHCH(OH)NH, it had not been proven that 1-aminoethanol contained a hydroxyl (-OH) group until Schiff's investigation in 1877. See: Schiff, Robert (1877) "Zur Constitution des Chloralammoniaks und des Aldehydammoniaks," Berichte der Deutschen Chemischen Gesellschaft, 10 : 165–171. Aschan, Ossian (1915) "Neues über Aldehyd-ammoniak und Chloral-ammoniak." Berichte der Deutschen Chemischen Gesellschaft, 48 (1) : 874–891.
References