Figure 1.
(A) Structural drawing of 1 in the crystal showing the atom numbering system. (B) Bond distances (Å) and angles (°)found in the X-ray crystallographic structure of 1,1′-bipyrrole (1) with the numbering system used. The atoms of the leftmost pyrrole ring lie in a plane, as do those of the rightmost. The C(2)-N(1)-N(1A)-C(5A) torsion angle was found to be ∼80°, and the C(5)-N(1)-N(1A)-C(5A) torsion angle is ∼100°. (C) Packing arrangement of 1 in the crystal.