Estimation of the relative stability of chair forms of hexahydropyrimidine

  • V. V. Kuznetsov


Nonempirical approximations HF/6-31G(d), MP2/6-31G(d)//HF/6-31G(d), PBE/3z, and RI-MP2/λ2 were applied to the calculation of the relative stability and parameters of the conformational equilibrium of three chair forms of the unsubstituted hexahydropyrimidine with different orientation of the N-H bonds. It was established that in the framework of the used methods the most stable are the conformers of diaxial and axial-equatorial chairs. The occupancy of the diequatorial chair form at the room temperature does not exceed 1.7%.


Imaginary Frequency Oxazine Conformational Equilibrium Chair Form Chair Conformer 
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Copyright information

© Pleiades Publishing, Ltd. 2011

Authors and Affiliations

  1. 1.Institute of Physics of Molecules and Crystals, Ufa Scientific CenterRussian Academy of SciencesUfaRussia
  2. 2.Ufa State Oil Technical UniversityUfaRussia

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