The Hydrogen-Bonded 2-Pyridone Dimer Model System. 1. Combined

Jul 1, 2010 - thymine.12,14 The cyclic amide PD is subject to lactam-lactim tautomerism, whereby 2-hydroxypyridine (HP) is formed (Scheme. 1). In the ...
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J. Phys. Chem. A 2010, 114, 7749–7760

7749

The Hydrogen-Bonded 2-Pyridone Dimer Model System. 1. Combined NMR and FT-IR Spectroscopy Study Łukasz Szyc,† Jing Guo,‡ Ming Yang,† Jens Dreyer,† Peter M. Tolstoy,‡ Erik T. J. Nibbering,*,† Bogusława Czarnik-Matusewicz,§ Thomas Elsaesser,† and Hans-Heinrich Limbach‡ Max Born Institut fu¨r Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Strasse 2A, D-12489 Berlin, Germany, Institut fu¨r Chemie und Biochemie, Freie UniVersita¨t Berlin, Takustrasse 3, D-14195 Berlin, Germany, and Faculty of Chemistry, UniVersity of Wrocław, F. Joliot-Curie 14, 50-383 Wrocław, Poland ReceiVed: April 22, 2010; ReVised Manuscript ReceiVed: June 08, 2010

2-Pyridone (PD), converting to 2-hydroxypyridine (HP) through a lactam-lactim isomerization mechanism, can form three different cyclic dimers by hydrogen bond formation: (PD)2, (PD-HP), and (HP)2. We investigate the complexation chemistry of pyridone in dichloromethane-d2 using a combined NMR and Fourier transform infrared (FT-IR) approach. Temperature-dependent 1H NMR spectra indicate that at low temperatures (