Etude spectroscopique quantitative de l'ecart a la planeite du systeme conjugue dans les molecules d'α-enones R1COCR2CH2
作者:A. Bienvenue
DOI:10.1016/0040-4020(72)84043-2
日期:1972.1
UV, NMR and IR spectra of 9 αβ-unsaturated ketones R1COCR2CH2 have been studied, where R1 and R2 are Me, Et, i-Pr, t-Bu or neo-Pe groups. UV and especially IR spectroscopy give more useful information than NMR spectroscopy. When R1 = Me, Et, i-Pr or t-Bu and R2 = Me, an equilibrium exists between the s-trans and a twisted conformation in which the diedral angle between the two π systems is about 120°
UV,NMR和9αβ不饱和酮IR光谱- [R 1 COCR 2 CH 2进行了研究,其中,R 1和R 2是Me,ET,I-PR,叔卜或新Pe的组。与NMR光谱相比,UV光谱(尤其是IR光谱)提供了更多有用的信息。当R 1 = Me,Et,i-Pr或t-Bu且R 2 = Me时,s- trans和扭曲构象之间存在平衡,其中两个π系统之间的死角约为120°。当R 1 = t-Bu和R 2 = Et,i-Pr,t-Bu或neo-Pe时,两个扭曲构象处于平衡状态。在任何情况下是S-任何明显的量顺 观察到的构象。