Structure/energy correlation of bowl depth and inversion barrier in corannulene derivatives: Combined experimental and quantum mechanical analysis
Structure/energy correlation of bowl depth and inversion barrier in corannulene derivatives: Combined experimental and quantum mechanical analysis
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DOI：
10.1021/ja0019981
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发表时间：
2001-01-31
影响因子：
15
通讯作者：
Siegel, JS
中科院分区：
文献类型：
--
作者：
Seiders, TJ;Baldridge, KK;Siegel, JS
一系列具有不同碗深度的冠环烯衍生物的合成使得可以研究结构（碗深度）和碗反转能量的相关性。放置在周边位置的取代基具有排斥性并使碗变平，从而导致碗翻转势垒降低。相反，穿过周边位置的退火会导致碗加深，从而增加碗反转势垒。已经测量了 8.7 到 17.3 kcal/mol 之间的势垒，并使用各种从头计算方法计算了它们的结构。假设单个球轮烯导数的能量分布符合混合四次/二次函数，从中导出遵循四次函数的碗深度和反转势垒的经验相关性。这种类型的结构/能量关联广泛地说明了底物的酶促和催化活化的性质。
Synthesis of a series of corannulene derivatives with varying bowl depths has allowed for a study correlating the structure (bowl depth) and the energy of bowl inversion. Substituents placed in the peri positions are repulsive and flatten the bowl, thus causing a decrease in the bowl inversion barrier. Conversely, annelation across the peri positions causes a deepening of the bowl, thus an increase in the bowl inversion barrier. Barriers between 8.7 and 17.3 kcal/mol have been measured, and their structures have been calculated using a variety of ab initio methods. The energy profile of an individual corannulene derivative is assumed to fit a mixed quartic/quadratic function from which an empirical correlation of bowl depth and inversion barrier that follows a quartic function is derived. Structure/energy correlations of this type speak broadly of the nature of enzymatic and catalytic activation of substrates.