Control of the conformational equilibria in aza-cis-decalins: structural modification, solvation, and metal chelation.
Control of the conformational equilibria in aza-cis-decalins: structural modification, solvation, and metal chelation.
复制标题
氮杂顺式十氢萘构象平衡的控制：结构修饰、溶剂化和金属螯合。
DOI：
10.1021/jo025544t
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
Kozlowski,MarisaC
中科院分区：
文献类型：
--
作者：
Phuan,Puay-Wah;Kozlowski,MarisaC
合成了一系列氨基醇和二氨基萘烷，并研究了它们的构象性质。通过NMR光谱测量构象异构体的平衡分布。平衡比取决于十氢萘环系统和溶剂上的取代基的位置。7位取代的1-氮杂-顺式-萘烷比5位取代的类似物更可能采用N-形式。N-in形式通常在非极性溶剂中有利，而N-out形式在极性溶剂中有利。络合与LiClO 4和Et 2 Zn改变平衡，有利于N-在十氢萘构象。这两种构象配位锂离子，使得“开/关”的构象转换，没有观察到这些十氢化萘。比较结果与络合研究（−）-金雀花碱允许一个理想的“开/关”构象开关的标准进行定义。
A series of amino alcohol- and diamino-cis-decalins were synthesized and their conformational properties investigated. The equilibrium distributions of the conformational isomers were measured via NMR spectroscopy. The equilibrium ratios depend on the position of the substituents on the decalin ring system and the solvent. The 7-substituted 1-aza-cis-decalins are more likely to adopt the N-in form than the 5-substituted analogues. The N-in form is generally favored in nonpolar solvents, while the N-out form is favored in polar solvents. Complexation with LiClO4and Et2Zn alters the equilibrium to favor the N-in decalin conformer. Both conformers coordinate lithium ions such that “on/off” conformational switching is not observed for these decalins. Comparison of the results with complexation studies of (−)-sparteine allows the criteria for an ideal “on/off” conformational switch to be defined.