N-Heterocyclic Carbene-Catalyzed Atroposelective Synthesis of Pyrrolo3,4-bpyridines with Configurationally Stable C–N Axial Chirality

The first atroposelective synthesis of pyrrolo3,4-bpyridines catalyzed by N-heterocyclic carbene has been achieved. A wide range of chiral atropisomers of pyrrolo3,4-bpyridines were obtained in high yields with excellent enantioselectivities (96-99% enantiomeric excess). The experimental results and density functional theory calculations showed that the C-N axial chirality of the product had high thermal stability.