Dipartimento di Chimica and Nanostructured Interfaces and Surfaces (NIS) Centre, Università degli Studi di Torino, via P. Giuria 7, IT-10125 Torino, Italy.
Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Via Elce di Sotto 8, I-06123 Perugia, Italy.
Molecules. 2020 May 12;25(10):2274. doi: 10.3390/molecules25102274.
Formamide has been recognized in the literature as a key species in the formation of the complex molecules of life, such as nucleobases. Furthermore, several studies reported the impact of mineral phases as catalysts for its decomposition/polymerization processes, increasing the conversion and also favoring the formation of specific products. Despite the progresses in the field, in situ studies on these mineral-catalyzed processes are missing. In this work, we present an in situ UV-Raman characterization of the chemical evolution of formamide over amorphous SiO samples, selected as a prototype of silicate minerals. The experiments were carried out after reaction of formamide at 160 °C on amorphous SiO (Aerosil OX50) either pristine or pre-calcined at 450 °C, to remove a large fraction of surface silanol groups. Our measurements, interpreted on the basis of density functional B3LYP-D3 calculations, allow to assign the spectra bands in terms of specific complex organic molecules, namely, diaminomaleonitrile (DAMN), 5-aminoimidazole (AI), and purine, showing the role of the mineral surface on the formation of relevant prebiotic molecules.
甲酰胺在文献中被认为是形成生命复杂分子（如核碱基）的关键物质。此外，有几项研究报告了矿物相作为其分解/聚合过程的催化剂的影响，这增加了转化率，并有利于特定产物的形成。尽管该领域取得了进展，但这些矿物催化过程的原位研究仍然缺乏。在这项工作中，我们对无定形 SiO 样品上的甲酰胺的化学演化进行了原位 UV-Raman 表征，选择无定形 SiO（Aerosil OX50）作为硅酸盐矿物的原型。实验是在 160°C 下将甲酰胺与无定形 SiO（Aerosil OX50）反应后进行的，该无定形 SiO 样品要么是原始的，要么是在 450°C 下预先煅烧的，以除去大部分表面硅醇基团。我们的测量结果基于密度泛函 B3LYP-D3 计算进行解释，允许根据特定的复杂有机分子（即二氨基丙二腈（DAMN）、5-氨基咪唑（AI）和嘌呤）来分配谱带，表明矿物表面在形成相关前生物分子方面的作用。
