Dataset for: Very Low Temperature Dynamic 29Si NMR Study of the Conformational Equilibrium of (1,1'-Phenyl-1,1'-silacyclohex-1-yl)disiloxane

The conformational equilibrium of (1,1'-phenyl-1,1'-silacyclohex-1-yl)disiloxane has been studied by very low temperature 29Si NMR spectroscopy while both 1H and 13C NMR spectroscopy along the same temperature range failed. The barrier to six-membered ring interconversion ΔG#/kcal/mol and the conformational equilibrium of the ax-ax, ax-eq and eq-eq conformers could be analyzed. Both assignment of the 29Si signals and quantification of the conformational equilibrium is supported by MP2 and DFT calculations.

本研究采用极低温29Si核磁共振（29Si NMR）波谱法，对(1,1'-苯基-1,1'-硅环己基)二硅氧烷的构象平衡展开了探究；而在相同温度区间内开展的1H与13C核磁共振波谱研究则未能获取有效实验数据。研究可成功解析六元环互变的吉布斯自由能能垒ΔG#/千卡/摩尔，以及直立-直立（ax-ax）、直立-平伏（ax-eq）与平伏-平伏（eq-eq）三类构象体的构象平衡参数。29Si信号的归属以及构象平衡的定量分析结果，均得到了二级莫勒-普莱塞特微扰理论（MP2）与密度泛函理论（DFT）计算的支持。