Reactivity of planar and twisted amides in vacuum and aqueous environments: an ab initio MEP study

Abstract

We present an ab initio study on the amide resonance in vacuo and water environments. The planar cis and trans minima, as well as the syn and anti twisted conformations of N-methylacetamide (NMA) were fully optimized at the 6–31G* level. Ab initio 6–31G* wavefunctions obtained from in vacuo and self-consistent reaction field calculations were used to compute the corresponding molecular electrostatic potentials for the four conformations of NMA in gas phase and water. Finally, MEP difference maps, and electrostatic charges were used to study the changes in the charge distribution occurring when the NMA molecule interacts with a hydride molecule placed in the surroundings the amide hydrogen.