Hydrogen-bond symmetry in zwitterionic phthalate anions: symmetry breaking by solvation

CL Perrin, JS Lau

Index: Perrin, Charles L.; Lau, Jonathan S. Journal of the American Chemical Society, 2006 , vol. 128, # 36 p. 11820 - 11824

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Citation Number: 43

Abstract

The cationic nitrogen of zwitterion 1 is located symmetrically with respect to its intramolecular OHO hydrogen bond. Incorporation of one 18O allows investigation of the H- bond symmetry by the NMR method of isotopic perturbation. In both CD3OD and CD2Cl2 equilibrium isotope shifts are detected at the carboxyl and ipso carbons. Therefore, 1 exists as a pair of interconverting tautomers, not as a single symmetric structure with its ...