Pyramidal nitrogen inversion hindered by a strong intramolecular hydrogén bond in 2-diethylaminomethylphenols

✍ Scribed by G. S. Denisov; V. A. Gindin; N. S. Golubev; A. I. Koltsov; S. N. Smirnov; M. A. And L. Rospenk Koll Sobczyk

• Book ID: 102526851
• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 330 KB
• Volume: 31
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1260311116

✦ Synopsis

Abstract

In the ^1^H NMR spectra of 2‐diethylaminomethyl‐3,4,6‐trichlorophenol (1) below 260 K, an additional splitting of the CH~2~ signal was found, which can be ascribed to the hindered nitrogen inversion. In the molecule of the O‐methylated derivative (2) this process is fast (on the NMR time‐scale) down to 150 K. The frequencies and the activation parameters of the nitrogen inversion in (1) were measured by DNMR, which indicated that the inversion requires a preliminary stage of breaking an intramolecular hydrogen bond. The activation enthalpy, δ__H__, of the inversion stage was evaluated as 28.5 ± 6.7 kJ mol^−1^.