A facile, efficient, and economical synthesis of both β-proline enantiomers starting
from trans-4-hydroxy-l-proline is reported. Light-promoted radical Barton decarboxylation and nitrile introduction
at C4 followed by hydrolysis gives the desired products in high optical purity. These
routes should be of interest to those seeking economical access to β-proline for multiple
applications.
Key words
beta-proline - hydroxyproline - radical decarboxylation - organo-catalyst