Experimental and theoretical evaluation of trans-3-halo-2-hydroxy-tetrahydropyran conformational preferences. Beyond anomeric interaction
作者:Thaís M. Barbosa、Renan V. Viesser、Raymond J. Abraham、Roberto Rittner、Cláudio F. Tormena
DOI:10.1039/c5ra04968g
日期:——
basis set. Theoretical calculations taking into account the solvent effect (CHCl3 and DMSO) were performed using the IEFPCM solvent model, M06-2X/aug-cc-pVTZ level of theory for C, H and O atoms and M06-2X/aug-cc-pVDZ-PP with pseudopotential for the iodine atom. NBO, QTAIM and NCI analyses were applied to identify which stereoelectronic interactions are responsible for their conformational preferences
通过NMR光谱和电子结构计算研究了反式-3-X-2-羟基-四氢吡喃(X = F,Cl,Br,I)中的构象异构现象。通过1 H,13 C和选择性TOCSY NMR光谱以及HSQC,COZY和NOESY等高线图对化合物进行合成,纯化和鉴定。使用Mug-2cc混合功能(DFT)和MP2(从头算)方法以及aug-cc-pVTZ基集,计算出分离出的分子中最稳定构象异构体的几何构型和构象异构体能量。考虑溶剂效应的理论计算(CHCl 3(DMSO和DMSO)使用IEFPCM溶剂模型,C,H和O原子的理论理论水平为M06-2X / aug-cc-pVTZ和碘原子为准电势的M06-2X / aug-cc-pVDZ-PP进行。NBO,QTAIM和NCI分析用于确定哪些立体电子相互作用是其构象偏好的原因。构象剂稳定性在溶剂存在下改变。端基异构作用似乎对这些分子中的分子构象没有显着影响。