B21C7与DB21C7分子构象溶剂效应NMR研究

^(1)H NMR Spectra of Solvent Effects on the Molecular Conformations of B21C7and DB21C7

通过^(1)H NMR核磁波谱学方法研究了芳香冠醚B21C7和DB21C7构象的溶剂效应。结果表明,CD_(3)CN分子与两种芳香冠醚的苯环取代基存在CH^(+)…N相互作用,CD_(3)OD与冠醚环存在OH^(+)…O相互作用。由于不同溶剂分子的作用引起苯环取代基与冠醚环的相对位置改变,冠醚环在苯环取代基的屏蔽区域和去屏蔽区域间变化,产生了相应化学位移差异。

The solvent effects on the conformations of aromatic crown ethers B21C7and DB21C7are studied by^(1)H NMR spectroscopy.The results show that in the two aromatic crown ethers,the CH^(+)…N interaction exists between CD_(3)CN and phenyl ring substituents,and OH^(+)…O interaction exists between CD_(3)OD and the crown ether ring.Due to the solvent effects,the crown ether ring changes between the shielding area and the deshielding area of the phenyl ring substituent,resulting in the corresponding difference of chemical shifts.