C-N Coupling through Hydroaminoalkylation on a Single-Atom Rh Heterogeneous Catalyst
Yuting Li1, Yu Tang1, Franklin Feng Tao1
1Department of Chemical and Petroleum Engineering, University of Kansas, Lawrence, KS 66049, USA.
Abstract:
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 Rh1 atoms anchored on TiO2 (P25) nanoparticles designated as Rh1 /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 Rh1 O4 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 (Rh1 /P25) can be readily separated from reactants and products, reused for multiple runs of hydroaminoalkylation, and recycled with a low cost.
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