Hydroacridines: Part 23.1H and13C NMR spectra ofsym-octahydroacridine, its 9-(3-pyridyl) and 9-(4-pyridyl) derivatives and the correspondingN(10)-oxides. An experimental approach to the diamagnetic anisotropy of the pyridine nucleus
作者:Francisc Potmischil、C?lin Deleanu、Maria Marinescu、Mircea D. Gheorghiu
DOI:10.1002/mrc.996
日期:2002.3
provided the first experimental evidence of the difference in the anisotropy effect of the two non‐symmetrical moieties of the pyridine nucleus, and allowed us to ascertain that the shielding effect of the moiety defined by the C(2′)—N—C(6′) atoms is weaker than that of the C(3′)—C(4′)—C(5′) moiety. The 13C NMR spectra of 1–3 and 1a–3a and the effect of N(10)‐oxidation on the 13C NMR chemical shifts are
1,2,3,4,5,6,7,8-八氢吖啶 (1), 1,2,3,4,5,6,7,8-八氢吖啶 (1), 1,2,3,4,5,6,7,8-octahydro-9-( 3-吡啶基)吖啶 (2), 1,2,3,4,5,6,7,8-octahydro-9-(4-pyridyl)吖啶 (3) 和相应的 N(10)-氧化物 1a, 2a和 3a 分别是在 400 MHz 1H NMR 光谱和质子-质子解耦、HMQC 和 NOEDIFF 实验的基础上实现的。上述化合物的光谱数据提供了吡啶核的两个非对称部分的各向异性效应差异的第一个实验证据,并使我们能够确定由 C(2' )-NC(6') 原子比 C(3')-C(4')-C(5') 部分弱。还讨论了 1-3 和 1a-3a 的 13C NMR 光谱以及 N(10)-氧化对 13C NMR 化学位移的影响。2 和 3 与间氯过苯甲酸发生区域特异性的 N-氧化,得到不含