Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08903, USA.
Nat Chem. 2010 Apr;2(4):303-7. doi: 10.1038/nchem.577. Epub 2010 Feb 28.
Stereoselective chemical synthesis requires the two faces of a π bond to be differentiated. Theoretically sound qualitative models for understanding stereoinduction seem to break down in sterically unbiased cyclic systems. Presented here as the distortional asymmetry model is new insight that identifies circumstances where distortional ground state contributions are highly asymmetric and thereby contribute significantly to face selectivity. Out-of-plane distortional potential calculations, transition state calculations and molecular orbital analysis agree with experimental data that cannot otherwise be attributed to steric, torsion, polar or emergent transition state stabilizing effects. The model is readily understood in terms of reaction theory. The explanatory power of the model is also discussed.
立体选择性化学合成需要区分π键的两个面。用于理解立体诱导的理论合理定性模型在无空间位阻的环状体系中似乎失效。本文提出的扭曲非对称模型提供了新的见解，可识别出扭曲基态贡献高度不对称的情况，从而对面选择性有重要贡献。非平面扭曲势能计算、过渡态计算和分子轨道分析与实验数据一致，这些实验数据不能归因于空间位阻、扭转、极性或新兴过渡态稳定效应。该模型可以根据反应理论很容易地理解。还讨论了该模型的解释能力。
