Stable conformations of 12‐crown‐O3N and its Li+ complex in aqueous solution

Stable conformations of 12‐crown‐O3N and its Li complexes in aqueous solution were investigated. To calculate the free energy differences of conformers of 12‐crown‐O3N and its Li+ complex, our procedure was to make use of two programs, CONFLEX and BOSS. The former generates conformers, and the latter calculates the differences in free energy of solvation between two conformers in aqueous solution. It was confirmed that the present procedure is applicable in solving the question of what is the most stable conformation of 12‐crown‐O3N in aqueous solution. Results of the calculations suggest that the order of stability for conformers in a vacuum is different from that in aqueous solution. It was also confirmed that the coordination geometry of solvent waters to Li+ changes depending on the distance between the cation and the crown ring. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 1226–1235, 2002

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