Orde Q Munro1, Greville L Camp. 1. School of Chemical and Physical Sciences, University of Natal, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa. munroo@nu.ac.za
Abstract
The title Schiff base compound, N,N'-bis(pyrrol-2-ylmethylene)propane-1,2-diamine, C(13)H(16)N(4), forms an interesting supramolecular structure (a one-dimensional ladder-like polymer) in the solid state that is based on the existence of complementary intermolecular N-H.N=C hydrogen bonds between the monomer units. The polymer axis is collinear with the c axis of the orthorhombic unit cell. Quantum-chemical AM1 calculations clearly indicate that self-recognition in this system by hydrogen bonding is favoured on electrostatic grounds, since the partial atomic charge on the H atom of the pyrrole NH group (0.274 e) complements the partial atomic charge of the N atom of the C=N group (-0.239 e) on a neighbouring molecule.
The title Schiff base compound, n class="Chemical">N,N'-bis(pyrrol-2-ylmethylene)propane-1,2-diamine, C(13)H(16)N(4), forms an interesting supramolecular structure (a one-dimensional ladder-like polymer) in the solid state that is based on the existence of complementary intermolecular N-H.N=C hydrogen bonds between the monomer units. The polymer axis is collinear with the c axis of the orthorhombic unit cell. Quantum-chemical AM1 calculations clearly indicate that self-recognition in this system by hydrogen bonding is favoured on electrostatic grounds, since the partial atomic charge on the H atom of the pyrroleNH group (0.274 e) complements the partial atomic charge of the N atom of the C=N group (-0.239 e) on a neighbouring molecule.