University of Oklahoma, Stephenson Life Sciences Research Center 1 article published in JoVE Chemistry A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones Luca Scapinello1, Angelo Maspero1, Stefano Tollari1, Giovanni Palmisano1, Kenneth M Nicholas2, Andrea Penoni1 1 3-Aroyl-N-hydroxy-5-nitroindoles were synthesized by cycloaddition of 4-nitronitrosobenzene with a conjugated terminal alkynone in a one-step thermal procedure. Preparation of the nitrosoarene and of the alkynones were adequately reported and respectively through oxidation procedures on the corresponding aniline and on the alkynol.