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Graphical abstract Highlights • Transition-metal-free visible-light-induced trifluoromethylation of imidazopyridines. • Anthraquinone-2-carboxylic acid as the photo-organocatalyst. • Photoredox catalyzed cyclization generate trifluoromethyl radical. Abstract A transition-metal-free, visible-light-induced trifluoromethylation of imidazo[1,2- a ]pyridines has been developed at mild conditions by employing cheap and commercially available anthraquinone-2-carboxylic acid (AQN-2-CO 2 H) as the photo-organocatalyst, and Langlois reagent as the trifluoromethylating reagent. A series of 3-(trifluoromethyl)imidazo[1,2- a ]pyridine derivatives with broad functionalities could be conveniently and efficiently obtained by direct regioselective functionalization. [ABSTRACT FROM AUTHOR]

Abstract: A mild procedure for the conjugate addition of the trifluoromethyl anion to activated Michael acceptors such as arylidenemalononitriles (15 examples) and arylidene Meldrum’s acids (9 examples) using phenyl trifluoromethyl sulfone through a reductive magnesium metal mediated procedure is described. The new methodology is used to prepare befloxatone, a reversible and selective monoamine oxidase A inhibitor. [Copyright &y& Elsevier]

Abstract: Aryl(methoxy)(trifluoromethyl)boranes, generated in situ, readily react with ethyl diazoacetate and N-(4-methoxyphenyl)imines to give derivatives of β-amino acids. In this process, the electron-deficient borane reacts with the diazo compound followed by trapping of the intermediate boron enolate by the imine. The final products are predominantly produced as syn isomers. [Copyright &y& Elsevier]

Abstract: A small library of structurally diverse primary amines bearing a geminal CF3 group was synthesized on a preparative scale. The synthesis starts with an aldehyde or ketone that reacts with benzylamine yielding the corresponding imine. The latter is then trifluoromethylated with Me3SiCF3 under acidic conditions to give a benzylalkylamine. In the last step the Pd-mediated hydrogenation of the benzylalkylamines furnishes the title compounds. All synthetic steps are high-yielding; neither the isolation of the intermediates nor the chromatographic purification of the products is necessary. [Copyright &y& Elsevier]