Background: The complex photochemistry of aryl azides has fascinated scientists for several decades. Spectroscopists have investigated the intermediates formed by different analytical techniques. Theoretical chemists have explained the intrinsic interplay of intermediates under different experimental conditions. Objective & Method: A complete understanding of the photochemistry of a given fluoro aryl azide is a basic requisite for its use in chemistry. In this review, we will discuss the synthesis of several fluoro substituted aryl azides and the reactions and intermediates generated upon photolysis and thermolysis of these azides and some examples of their applications in photoaffinity labeling and organic synthesis. Conclusion: In spite of the extensive research on the photochemistry of fluoro aryl azides, there are some areas that remain to be investigated. The application of this reaction in the synthesis of novel heterocyclic compounds has not been fully studied. Since fluorophenyl azides are known to undergo C-H and N-H insertion reactions, they could be used to prepare new fluorinated molecules or in the biochemical process known as photoaffinity labeling.

Photochemical and photocatalytic oxidation of naproxen (NPX) with UV-A light and commercial TiO₂ under constant flow of oxygen have been investigated. Adsorption experiments indicated that 90% of the solute remained in the solution. Combined chemical analysis of samples on the photochemical degradation indicated that NPX in an aqueous solution (20 ppm) is efficiently transformed into other species but only 18% of the reactant is mineralized into CO₂ and water after three hours of reaction. Performing the photocatalytic oxidation in the presence of TiO₂, more than 80% of the organic compounds are mineralized by reactive oxidation species (ROS) within four hours of reaction. Analysis of reaction mixtures by a combination of analytical techniques indicated that naproxen is transformed into several aromatic naphthalene derivatives. These latter compounds are eventually transformed into polyhydroxylated aromatic compounds that are strongly adsorbed onto the TiO₂ surface and are quickly oxidized into low-molecular-weight acids by an electron transfer mechanism. Based on this and previous studies on NPX photocatalytic oxidation, a unified and complete degradation mechanism is presented.

Nitrated products are important since they are intermediates in the synthesis of other compounds, such as explosives, perfumes, dyes and plastics, among others, and they have an easy capacity to convert into other functional groups. The synthesis of compounds with biological activity that have a nitro group in their structure is relevant to improving and/or enhancing their effect. In this work, different methodologies for the nitration of naphthoquinone derivative compounds are presented. The nitration of 3-R-2-(phenylamino)-1,4-naphthoquinone derivatives was carried out with nitric acid and sulfuric acid; milder reaction conditions were also established by diluting the acids or performing the reaction with weaker acids. Other methodologies were tested using nitrate salts for mononitrate product synthesis. We used a solvent-free reaction with oxalic acid using 3-R-2-(phenylamino)-1,4-naphthoquinones (R=H, Br or Cl), noting that the electronegativity of the chlorine group is decisive for achieving nitration with good yields. Finally, a Michael addition was performed with some nitrated anilines. To obtain denitrated compounds in the ortho and para positions, the reaction with strong acids is feasible; however, for the formation of mononitrated products, the Michael-type addition is more convenient.

Several fluoro phenyl triazoles were synthesized using click chemistry between fluoro phenyl azides and phenyl acetylene. Under ultrasound irradiation, this synthetic procedure was performed with Cu (I) in the presence of 1,10-phenanthroline. It is fast with high yields of target compounds. In addition, fluoro phenyl triazoles were evaluated against Candida albicans. The inhibition percentage of yeast growth was investigated using different concentrations of triazoles. Compounds containing a fluorine atom in 2, 4, 2,6, and 2,4,6 positions inhibited a higher percentage of yeast growth. All of the triazoles showed inhibition of the yeast–mycelium transition, which was related to pathogenicity of yeast strain C. albicans.