The 13C signal assignments of the aromatic carbon atoms in α-tocopherol were confirmed using [methyl-13C] α-tocopherol. The 13C-NMR spectra of α-tocopherol alkyl ethers and 5-alkyl-2, 5, 7, 8-tetramethyl-2-(4, 8, 12-trimethyltridecyl) chroman-6 (5H)-ones, which are formed in the radical scavenging reaction of α-tocopherol with alkylradicals, were recorded and examined. In α-tocopherol and its alkyl ethers, C-5 is more shielded than nearly equivalent C-7. The chemical shift difference seems to be consistent with the reactivity difference between these carbon atoms, which is known as the"Mills-Nixon effect."
使用[甲基-13C]α-
生育酚确认了α-
生育酚中芳香碳原子的13C信号分配。记录并检查了α-
生育酚烷基醚和5-烷基-2,5,7,8-四甲基-2-(4,8,12-三甲基
十三烷基)色满-6(5H)-酮的13C-NMR光谱,这些化合物是在α-
生育酚与烷基自由基的自由基清除反应中形成的。在α-
生育酚及其烷基醚中,C-5比几乎等效的C-7更受屏蔽。
化学位移差异似乎与这些碳原子的反应性差异一致,这被称为“Mills-Nixon效应”。