Conformational Behavior of Methyl(3R)-3-{〔(3′R)-3′-Hydroxybutanoyl〕oxy}butanoate in Solutions:Effect of Intramolecular Hydrogen Bond

  • Li Jun
    The Institute of Physical and Chemical Research (RIKEN)
  • Uzawa Jun
    The Institute of Physical and Chemical Research (RIKEN)
  • Doi Yoshiharu
    The Institute of Physical and Chemical Research (RIKEN)

書誌事項

タイトル別名
  • Conformational Behavior of Methyl (3R)-3-{((3R)-3-Hydroxybutanoyl)oxy}butanoate in Solutions: Effect of Intramolecular Hydrogen Bond.
  • Conformational Behavior of Methyl 3R-3-
  • Conformational Behavior of Methyl (3<i>R</i>)-3-{[(3′<i>R</i>)-3′ -Hydroxybutanoyl]oxy}butanoate in Solutions: Effect of Intramolecular Hydrogen Bond

この論文をさがす

抄録

Methyl (3R)-3-{[(3′R)-3′-hydroxybutanoyl]oxy}butanoate (MHBOB) has been prepared as a model compound of the hydroxy terminal part of poly[(R)-3-hydroxybutanoate] [P(3-HB)]; the NMR assignments and conformational analyses of the compound are reported. The NMR assignments of MHBOB were made by means of two-dimensional pulsed field gradient 1H–1H COSY and 1H–13C HMBC (heteronuclear multiple-bond correlation) spectroscopy. The conformational behavior of MHBOB generated by rotation about two CH2–CH bonds was investigated in chloroform and in aqueous solution at various temperatures by analysis of vicinal coupling in the 500-MHz 1H NMR spectra. In both chloroform and aqueous solution, the monomer unit adjacent to the methoxy group was found to adopt a similar conformational distribution to that of the P(3-HB) polymer backbone, in which the trans and gauche conformers were predominant, while the another gauche conformer was suppressed to almost zero. On the other hand, the monomer unit adjacent to the hydroxy group had a different conformational distribution relative to that of the other monomer unit, due to the formation of an intramolecular hydrogen bond between hydroxy and carbonyl groups. In chloroform, only the gauche conformer was predominant at temperatures between −60 and 57 °C, and even the fraction of another gauche conformer was higher than that of trans conformer at low temperatures below 0 °C. In aqueous solution, the fraction of gauche conformer was also higher than that of trans conformer, suggesting the formation of the intramolecular hydrogen bond. However, the formation of the intramolecular hydrogen bond in aqueous solution was not so strong as that in chloroform.

収録刊行物

被引用文献 (6)*注記

もっと見る

参考文献 (48)*注記

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ