Mihaela Gulea

A series of 3‐allenyl benzo[b]thiophenes were synthesized through a gold(I)‐catalyzed domino reaction. The process consists in a 5‐ endo ‐dig cyclization with C−S bond formation and consecutive S‐to‐C propargyl migration via [3,3]‐sigmatropic Claisen rearrangement. With aryl substituents on both triple bonds of the substrate, subsequent intramolecular hydroarylation on the formed allenyl system led to 3‐indenyl benzo[b]thiophenes. From a substrate bearing a 3‐butynol moiety diverse fused O ‐heterocycles have been obtained via intramolecular hydroalkoxylation. A gold‐mediated 1,3‐migration involving allenyl to propargyl rearrangement is also described. magnified image

The hetero-Diels–Alder reaction involving a dithioester and a radiofluorinated diene as a novel prosthetic group was used as a catalyst-free click-reaction for the indirect 18 F-labelling of peptides and applied to a PSMA-ligand for in vivo imaging.