Development of anodic modification reaction of N-acryloyl-proline derivatives using lithium perchlorate-nitromethane system

A facile electrochemical method for modification of the 5-position in N-acryloyl-proline methyl ester (N-Acr-Pro-OMe), followed by post-functionalization at the N-terminus by conjugate addition, was developed using anodic modification in a LiClO₄-MeNO₂ system. Anodic insertion of carbon and sulfur nucleophiles at the 5-position of N-Acr-Pro-OMe was carried out, with the N-acryloyl group remaining intact. Furthermore, a retained N-acryloyl group in the 5-modified proline was transformed by subsequent conjugate addition using thiols, which allowed the introduction of distinct functional groups between the 5-position and the N-terminus.