Facial Selectivity in the Diels-Alder Reactions of 2,2-Disubstituted Cyclopent-4-ene-1,3-dione Derivatives and a Computational Examination of the Facial Selectivity of the Diels-Alder Reactions of Structurally Related Dienes and Dienophiles
作者:Pei-Ying Liu、Yong-Jin Wu、Cory C. Pye、Paul D. Thornton、Raymond A. Poirier、D. Jean Burnell
DOI:10.1002/ejoc.201101301
日期:2012.2
of the plane-nonsymmetric dienophiles spiro[bicyclo[2.2.2]octane-2,1′-[3]cyclopentene]-2′,5′-dione (6) and spiro[bicyclo[2.2.1]heptane-2,1′-[3]cyclopentene]-2′,5′-dione (7) has been found to be very similar to the facial selectivity of reactions of cyclopentadienes fused to bicyclo[2.2.2]octane and bicyclo[2.2.1]heptane (4 and 5). This is strong evidence for steric control in their facial selectivities
通过平面非对称亲二烯体螺[双环[2.2.2]辛烷-2,1'-[3]环戊烯]-2',5'-二酮的内过渡态进行的Diels-Alder反应中的面部选择性(6)和螺[bicyclo[2.2.1]heptane-2,1'-[3]cyclopentene]-2',5'-dione (7) 已被发现与环戊二烯稠合到双环的反应的面部选择性非常相似[2.2.2] 辛烷和双环 [2.2.1] 庚烷(4 和 5)。这是他们面部选择性中空间控制的有力证据。涉及这些化合物反应的密度泛函计算以及一系列构象锁定模型加数(26a-c 和 27a-c)揭示了几何和能量特性,证实了面部选择性受空间效应控制。空间相互作用似乎是亲二烯体 6 的内/外选择性低的原因,