Influence of calculation level and effect of methylation on axial/equatorial equilibria in piperidines

  title={Influence of calculation level and effect of methylation on axial/equatorial equilibria in piperidines},
  author={Luis Carballeira and Ignacio P{\'e}rez-Juste},
  journal={Journal of Computational Chemistry},
A detailed conformational analysis was performed on the chair forms of piperidine, N‐methylpiperidine, and some methylated derivatives using Hartree–Fock (HF) and MP2 ab initio methods with several basis sets (from 3–21G to 6–311++G**), and the most widely used semiempirical approaches (MNDO, AM1, and PM3). It was found that the use of polarized basis sets at the HF level is adequate enough for the prediction of conformational preferences in the axial/equatorial equilibrium of the N‐R group in… 

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