On the Stabilization of the <i>Syn</i>-Rotamer of Amino Acid Carbamate Derivatives by Hydrogen Bonding

Abstract

The syn -rotamers of carbamate derivatives of α-amino acids are shown to be stabilized by the formation of H-bond complexes with carboxylic acid moieties in solution. This effect is, as expected, concentration and temperature dependent. Thermodynamic parameters (both Δ G ° and Δ G ‡ ) for N -Boc-alanine were determined by NMR in the ±60 °C range.