Quinones were firstly used as dipolarophiles in a photoclick 1,3‐cycloaddition with 2,5‐diaryltetrazoles, as photoactivatable predipoles, providing a novel and efficient access to three types of pyrazole‐fused quinones (indazoledione derivatives). Distinctive features of this protocol include the use of light as the unique reagent and readily available, stable, and easy to handle starting materials and good to excellent yields. Photophysical and electrochemical properties of the quinones and their potential application as photoredox catalysts are also detailed.

Lewis acid catalyzed Friedel-Crafts alkylation of indoles has been achieved in high yields and selectivities using p-quinols as electrophiles. (S)-Binol-3,3'-(9-anthracenyl)-phosphoric acid was able to catalyze the enantioselective formation of 5-(3-indole)-2-cyclohexenone derivatives. Experimental results and theoretical calculations explained the enantioselectivity based on a transition state where two water molecules act as a tether joining the p-quinol with the phosphoric acid and the NH of indole, thus facilitating the desymmetrization of the prochiral cyclohexadienone framework.

A straightforward methodology for the regioselective synthesis of pyrazoles has been developed by a domino sequence based on a photoclick cycloaddition followed by a photocatalyzed oxidative deformylation reaction. Distinguishing features of this protocol include an unprecedented photoredox-catalyzed Norrish type fragmentation under green-light irradiation and the use of α,β-unsaturated aldehydes as synthetic equivalents of alkynes, where the aldehyde is acting as a novel photoremovable directing group.

Unprecedented reactivity between naphthoquinone and β‐aryl‐α‐keto acids has been uncovered. The process combined the redox properties of the Michael‐type naphthoquinone acceptor with arylpyruvic acid, which is acting first as a C3‐donor pro‐nucleophile and later as an acylating agent. As a result, densely substituted naphthofuran‐2(3H)‐ones were generated in a mild and simple one‐pot reaction.

5‐Indolyl substituted 4‐hydroxy‐4‐methyl‐2‐cyclohexanone systems are prepared in a high π‐facial diastereoselective manner.