As further benefit not only aniline as a top 100 building block chemical is generated but also quinoline derivatives such as quinaldine can be obtained through subsequent acid catalyzed steps. Quinoline derivatives are applied in the synthesis of pharmaceutically relevant compounds such as quinolineartemisinine hybrids as anti-malaria drug. Figure : Reaction network of the photocatalytic reduction of nitrobenzene in ethanol. Blue arrows: Photocatalytic reaction; black boxes: major intermediates/products: (1) nitrobenzene, (2) nitrosobenzene, (3) phenylhydroxylamine, (4) aniline, (5) ethanol, (6) acetaldehyde, (7) azoxybenzene, (8) azobenzene, (9) 1,2-diphenylhydrazine, (10) ethylideneaniline, (11) ethylvinylether, (12) 4-ethoxy-1,2,3,4-tetrahydroquinaldine, (13) 1,2-dihydroquinaldine, (14) quinaldine, (15) 1,2,3,4tetrahydroquinaldine. The current world-wide production of aniline is based on the thermally initiated catalytic hydrogenation of nitrobenzene. Quinoline derivatives are either extracted from coal tar or synthesized in multi-step reactions such as Doebner-Miller or Skraup synthesis. These reactions make stochiometric use of oxidation and reduction agents as well as heavy-metal-compounds thereby generating significant amounts of unwanted side products. In contrast to these harsh conditions, the photocatalytic route is operated at room-temperature as onepot synthesis applying TiO2, an extensively studied, commercially available photocatalyst. For the reaction only nitrobenzene, TiO2 and ethanol are required. To obtain quinaldine, low amounts of acid are typically added to speed up acid catalyzed ring formations. Ideally, only water would be generated as side product.