High‐Energy Proton‐Beam‐Induced Polymerization/Oxygenation of Hydroxynaphthalenes on Meteorites and Nitrogen Transfer from Urea: Modeling Insoluble Organic Matter?

Formation and structural modification of oxygenated polycyclic aromatic hydrocarbons (oxyPAHs) by UV irradiation on minerals have recently been proposed as a possible channel of PAH transformation in astrochemical and prebiotic scenarios of possible relevance for the origin of life. Herein, it is demonstrated that high‐energy proton‐beam irradiation in the presence of various meteorites, including stony iron, achondrite, and chondrite types, promotes the conversion of two representative oxyPAH compounds, 1‐naphthol and 1,8‐dihydroxynaphthalene, to complex mixtures of oxygenated and oligomeric derivatives. The main identified products include polyhydroxy derivatives, isomeric dimers encompassing benzofuran and benzopyran scaffolds, and, notably, a range of quinones and perylene derivatives. Addition of urea, a prebiotically relevant chemical precursor, expanded the range of identified species to include, among others, quinone diimines. Proton‐beam irradiation of oxyPAH modulated by nitrogen‐containing compounds such as urea is proposed as a possible contributory mechanism for the formation and processing of insoluble organic matter in meteorites and in prebiotic processes. Meteor chemistry: Complex mixtures of oxygenated and oligomeric derivatives are produced from 1‐naphthol and 1,8‐dihydroxynaphthalene in the presence of meteorites on irradiation with a proton beam mimicking the solar wind. Addition of urea as a prebiotically relevant compound expanded the range of products. Thus, proton‐beam irradiation of oxygenated polycyclic aromatic hydrocarbons modulated by N‐containing compounds such as urea is a possible contributory mechanism for the formation of insoluble organic matter in meteorites and in prebiotic processes.