Pyrrole-substituted α, ω-diamines varying in length and number of heteroatoms between the amine functionalities were reacted with 1, 1′-ferrocenedimethanol to form ansa-ferrocenes. 1H-NMR binding studies in a 2% dimethylsulfoxide-d6 solution of dichloromethane-d2 establish a correlation between the affinity for tetrabutylammonium dihydrogen phosphate and the number of heteroatoms in the diamine. Further support for this conclusion came ...