Alkorta Ibon, Elguero José, Limbach Hans-Heinrich, Shenderovich Ilja G, Winkler Tammo
Instituto de Química Médica, CSIC, Juan de la Cierva 3, E-28006 Madrid, Spain.
Magn Reson Chem. 2009 Jul;47(7):585-92. doi: 10.1002/mrc.2433.
In 1975 a large number of coupling constants were measured in 2-fluorobenzamide labeled with (15)N. Some of them were assigned to couplings through intramolecular N-H...F hydrogen bonds (HBs). These couplings change dramatically when CDCl(3) is replaced by DMSO-d(6). In this theoretical paper we provide density functional theory (DFT) calculations that justify the existence of a weak HB in the absence of solvent, while solvents that act as HB acceptors break down the intramolecular hydrogen bond (IMHB) of 2-fluorobenzamide. Atoms in molecules (AIM) analyses and Steiner-Limbach plots were used to analyze the structure of the compounds.
