The Regioselective and Diastereoselective Direct Addition of Amines to Alkenes Using a Tantalum-Ureate Hydroaminoalkylation Catalyst

An organometallic tantalum catalyst equipped with a ureate ligand achieves the atom-economic hydroaminoalkylation (HAA) reaction to regioselectively form Csp3–Csp3 bonds by adding C–H activated unprotected secondary amines across alkenes. The substrate scope of this catalyst includes a range of activated, unactivated, and conjugated terminal, geminal and internal alkenes with aromatic, aliphatic and N-heterocyclic amines. This broad diversity of compatible substrates illustrates that hydroaminoalkylation offers a useful solution to the longstanding challenge of identifying a general catalyst for directly and catalytically adding amines to alkenes. This catalyst mediates hydroaminoalkylation with controlled regioselectivity and also achieves the challenging dialkylation of select amines with superb diastereoselectivity, including the selective trans-dialkylation of N-heterocycles.