C-N Coupling through Hydroaminoalkylation on a Single-Atom Rh Heterogeneous Catalyst.

C-N coupling is significant for the synthesis of fine chemicals toward various applications. Hydroaminoalkylation of olefins is a tandem reaction of C-N coupling involving first the formation of an aldehyde through hydroformylation of an olefin and then the production of amine through reductive amination of the aldehyde. Here we report a stable, supported catalyst of singly dispersed Rh atoms anchored on TiO (P25) nanoparticles designated as Rh /P25. Its high activity for C-N coupling was demonstrated by six hydroaminoalkylations of olefins and amines with selectivity of higher than 90% for producing tertiary amines. The singly dispersed Rh O on P25 exhibit activity and selectivity for hydroaminoalkylation comparable or even higher than some reported molecular catalysts. In contrast to molecular catalysts, the Rh-based single-atom Rh heterogeneous catalysis (Rh /P25) can be readily separated from reactants and products, reused for multiple runs of hydroaminoalkylation, and recycled with a low cost.