Department of Chemistry, University of Hawaii, 2545 McCarthy Mall, Honolulu, HI, 96822, USA.
W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii, 2545 McCarthy Mall, Honolulu, HI, 96822, USA.
Nat Commun. 2022 Jan 19;13(1):375. doi: 10.1038/s41467-022-27963-z.
The Strecker Synthesis of (a)chiral α-amino acids from simple organic compounds, such as ammonia (NH), aldehydes (RCHO), and hydrogen cyanide (HCN) has been recognized as a viable route to amino acids on primordial earth. However, preparation and isolation of the simplest hemiaminal intermediate - the aminomethanol (NHCHOH)- formed in the Strecker Synthesis to even the simplest amino acid glycine (HNCHCOOH) has been elusive. Here, we report the identification of aminomethanol prepared in low-temperature methylamine (CHNH) - oxygen (O) ices upon exposure to energetic electrons. Isomer-selective photoionization time-of-flight mass spectrometry (PI-ReTOF-MS) facilitated the gas phase detection of aminomethanol during the temperature program desorption (TPD) phase of the reaction products. The preparation and observation of the key transient aminomethanol changes our perception of the synthetic pathways to amino acids and the unexpected kinetic stability in extreme environments.
从简单的有机化合物（如氨（NH）、醛（RCHO）和氰化氢（HCN））出发，通过施雷克合成（a）手性α-氨基酸，已被认为是原始地球上氨基酸的可行途径。然而，施雷克合成中形成的最简单的半亚胺中间体——氨基甲醇（NHCHOH）——甚至是最简单的氨基酸甘氨酸（HNCHCOOH）的制备和分离一直难以捉摸。在这里，我们报告了在低温甲胺（CHNH）-氧气（O）冰中暴露于高能电子时制备氨基甲醇的情况。异构体选择性光电离飞行时间质谱（PI-ReTOF-MS）有助于在反应产物的温度程序解吸（TPD）阶段检测气相中的氨基甲醇。关键瞬态氨基甲醇的制备和观察改变了我们对手性氨基酸合成途径的认识，以及在极端环境中出人意料的动力学稳定性。
