Stereoselectivity in Oxyallyl-Furan 4+3 Cycloadditions: Control of Intermediate Conformations and Dispersive Stabilisation with Evans' Oxazolidinones.
Stereoselectivity in Oxyallyl-Furan 4+3 Cycloadditions: Control of Intermediate Conformations and Dispersive Stabilisation with Evans' Oxazolidinones.
复制标题
羟基氟4+3个环加成中的立体选择性：控制中间构象和用埃文斯的恶唑烷酮稳定的稳定。
DOI：
10.1039/c0sc00280a
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发表时间：
2010-09-01
期刊：
影响因子：
8.4
通讯作者：
Hsung RP
中科院分区：
文献类型：
--
作者：
Krenske EH;Houk KN;Lohse AG;Antoline JE;Hsung RP
手性恶唑烷酮以前被认为通过底物一个面的空间拥挤来控制环加成立体选择性。我们发现，在草酰基的 4+3 环加成反应中，立体诱导是由稳定的 CH-π 相互作用引起的，从而导致恶唑烷酮更拥挤的表面发生反应。恶唑烷酮取代的乙氧基烯丙基与呋喃的 4+3 环加成的密度泛函理论计算建立了意想不到的过渡态构象和选择性的新解释。
Chiral oxazolidinones were previously thought to control cycloaddition stereoselectivity by steric crowding of one face of the substrate. We have discovered that in 4+3 cycloaddition reactions of oxallyls, the stereoinduction is caused instead by stabilising CH–π interactions that lead to reaction at the more crowded face of the oxazolidinone. Density functional theory calculations on the 4+3 cycloadditions of oxazolidinone-substituted oxyallyls with furans establish unexpected transition state conformations and a new explanation of selectivity.