Atroposelective Synthesis of 1,1′‐Bipyrroles Bearing a Chiral N−N Axis: Chiral Phosphoric Acid Catalysis with Lewis Acid Induced Enantiodivergence

We present herein a highly efficient atroposelective synthesis of axially chiral 1,1'-bipyrroles bearing an N-N linkage from simple hydrazine and 1,4-diones. Further product derivatizations led to axially chiral bifunctional compounds with high potential in asymmetric catalysis. For this chrial phosphoric acid (CPA)-catalyzed double Paal-Knorr reaction, an intriguing Fe(OTf)₃ -induced enantiodivergence was also observed.