Dynamic processes in N-acylated 1,2-dihydro-2,2,4-trimethylbenzo(h)quinoline: A comparative study by NMR spectroscopy and quantum chemistry
作者:Jaan Leis、Karel D. Klika、Kalevi Pihlaja、Mati Karelson
DOI:10.1016/s0040-4020(99)00168-4
日期:1999.4
The results of conformational studies on several N-acyl derivatives of 1,2-dihydro-2,2,4-trimethylbenzo(h)quinoline are reported. A comparative study by NMR spectroscopy and semiempirical quantum chemical modelling using the AM1 SCF method revealed that the nitrogen atom is pyramidal with a substantial out-of-plane torsion of the acyl group and that the molecules adopt the E conformation in the ground
报道了对1,2-二氢-2,2,4-三甲基苯并(h)喹啉的几种N-酰基衍生物进行构象研究的结果。通过NMR光谱学和使用AM1 SCF方法的半经验量子化学模型进行的比较研究表明,氮原子呈锥体状,酰基基团具有明显的平面外扭曲,并且分子在基态下呈E构象。同样,1 H NMR信号揭示了所有研究化合物的一对对映异构体的相互转化,ΔG ≠在56.1–74.1 kJ mol -1范围内。实验值ΔG ≠之间存在良好的相关性半经验AM1 SCF模型预测的Ea值和能垒E A。