Thermodynamic evaluation of aromatic CH/π interactions and rotational entropy in a molecular rotor

  1. Pérez-Estrada, S. 2
  2. Rodríguez-Molina, B. 2
  3. Xiao, L. 2
  4. Santillan, R. 1
  5. Jiménez-Osés, G. 2
  6. Houk, K.N. 2
  7. Garcia-Garibay, M.A. 2
  1. 1 Instituto Politécnico Nacional
    info

    Instituto Politécnico Nacional

    Ciudad de México, México

    ROR https://ror.org/059sp8j34

  2. 2 University of California Los Angeles
    info

    University of California Los Angeles

    Los Ángeles, Estados Unidos

    ROR https://ror.org/046rm7j60

Revista:
Journal of the American Chemical Society

ISSN: 0002-7863

Año de publicación: 2015

Volumen: 137

Número: 6

Páginas: 2175-2178

Tipo: Artículo

DOI: 10.1021/JA512053T SCOPUS: 2-s2.0-84923241376 WoS: WOS:000349807000007 GOOGLE SCHOLAR

Otras publicaciones en: Journal of the American Chemical Society

Resumen

A molecular rotor built with a stator formed by two rigid 9β-mestranol units having a 90° bent angle linked to a central phenylene rotator has an ideal structure to examine aromatic CH/π interactions. Energies and populations of the multiple solution conformations from quantum-mechanical calculations and molecular dynamics simulations were combined with variable-temperature (VT) 1H NMR data to establish the enthalpy of this interaction and the entropy associated with rotation about a single bond. Rotational dynamics in the solid state were determined via VT cross-polarization magic-angle spinning 13C NMR spectroscopy. © 2015 American Chemical Society.