Magn Reson Chem. 2011 May;49(5):253-7. doi: 10.1002/mrc.2724. Epub 2011 Jan 28.
Nine 3-aryl-5r-aryl-6t-carbethoxycyclohex-2-enones 2a-2i have been synthesized. For all these compounds, (1)H and (13)C NMR spectra have been recorded. For two compounds, 2D spectra have been recorded. The spectral data suggest that these compounds adopt sofa conformation in solution with H-5, H-6 and H-4t occupying axial-like positions and H-4c occupying equatorial-like positions. In 3-phenyl-5r-(o-chlorophenyl)-6t-carbethoxycylohex-2-enone (2b), the o-chlorophenyl group is oriented such that the chlorine atom is in between H-4c and H-5. Allylic coupling of H-2 is observed only with H-4t. Evidence has been obtained for four-bond coupling between 1,3-diaxial and 1,3-axial-equatorial protons.
已经合成了 9 个 3-芳基-5r-芳基-6t-羧酸乙酯基环己-2-烯酮 2a-2i。对于所有这些化合物，都记录了 (1)H 和 (13)C NMR 谱。对于两个化合物，还记录了 2D 谱。光谱数据表明，这些化合物在溶液中采用沙发构象，H-5、H-6 和 H-4t 占据轴向位置，H-4c 占据类似的赤道位置。在 3-苯基-5r-(邻氯苯基)-6t-羧酸乙酯基环己-2-烯酮 (2b) 中，邻氯苯基基团的取向使得氯原子位于 H-4c 和 H-5 之间。仅观察到 H-2 与 H-4t 的烯丙偶合。已经获得了 1,3-二轴向和 1,3-轴向-赤道质子之间四键偶合的证据。
