Experimental and ab initio computational studies of self-association: 2-Aminopyridine and 3-aminopyridine

The self-association of 2-aminopyridine (2AP) in deuterated chloroform (CDCl₃) and deuterated dimethyl sulfoxide (DMSO-d₆) and 3-aminopyridine (3AP) in CDCl₃ have been studied experimentally by ¹H nuclear magnetic resonance spectroscopy. At 291 K, the measured association constants for 2AP are found to be 0.166 and 0.0229 lmol ^-1 in CDCl₃ and DMSO-d₆, respectively, whereas the association constant for 3AP in CDCl₃ is 0.271 l mol ^-1. To rationalise the experimental data, ab initio computational methods have been employed to identify the dimer structures which are of major importance in these self-association processes. In addition, the performance of continuum solvation models applied to 2AP association have been evaluated. © 2003 Elsevier B.V. All rights reserved.