Theoretical and infrared studies on the conformational isomerism of trans-2-bromo-alkoxycyclohexanes
作者:Josué M. Silla、Claudimar J. Duarte、Matheus P. Freitas、Teodorico C. Ramalho、Rodrigo A. Cormanich、Francisco P. Santos、Cláudio F. Tormena、Roberto Rittner
DOI:10.1016/j.saa.2011.06.023
日期:2011.10
The infrared spectra of trans-2-bromo-alkoxycyclohexanes (alcoxy = OMe, OEt, O(i)Pr and O(t)Bu) were obtained for the neat liquid, and the C-Br stretching mode was quantitatively analyzed to give insight about the conformational isomerism of these compounds. Frequency calculations supported the band assignments, and the relative band intensities suggest that the diaxial conformer is prevalent for the
获得了纯净液体的反式-2-溴-烷氧基环己烷(烷氧基= OMe,OEt,O(i)Pr和O(t)Bu)的红外光谱,并对C-Br拉伸模式进行了定量分析以提供洞察力关于这些化合物的构象异构性。频率计算支持频带分配,并且相对频带强度表明,二轴构象异构体在甲氧基和叔丁氧基衍生物中占主导地位(分别为51%和56%),而乙二酮构象形式在乙氧基和异丙氧基衍生物中占优势(76和77%)。因此,烷氧基的大小在确定标题化合物的构象偏好中起决定作用。