Cobalt-catalyzed carbonylative synthesis of free (NH)-tetrahydro-β-carbolinones from tryptamine derivatives

Abstract

A new cobalt-catalyzed carbonylative synthesis of free (NH)-tetrahydro-β-carbolinones from tryptamine derivatives has been developed. This reaction employs a cobalt(II) salt as the non-noble catalyst with TFBen as the CO source, and a variety of free (NH)-tetrahydro-β-carbolinones were produced in good yields using a traceless directing group strategy. Furthermore, late-stage modifications of several bioactive molecules (sorbic acid, probenecid, and febuxostat) could also be realized. The oxidant, silver salt, can be recycled and reused.