Asymmetric Latent Carbocation Catalysis with Chiral Trityl Phosphate
作者:Jian Lv、Qichao Zhang、Xingren Zhong、Sanzhong Luo
DOI:10.1021/jacs.5b11085
日期:2015.12.16
Stable carbocations such as tritylium ions have been widely explored as organic Lewisacid catalysts and reagents in organic synthesis. However, achieving asymmetric carbocation catalysis remains elusive ever since they were first identified over one century ago. The challenges mainly come from their limited compatibility, scarcity of chiral carbocations, as well as the extremely low barrier to racemization
Chiral Bis‐Oxalamide‐Rare Earth Complex Catalyzed Inverse‐ Electron‐Demand Asymmetric
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‐Hetero‐Diels‐Alder Reaction for Optically Active Dihydropyran Core Structures
作者:Hao‐Di Yang、Jun‐Bo Chen、Cheng Peng、Wen‐Kai Liu、Sheng‐Suo Zhou、Jia‐Xin Song、Zheng‐Hang Qi、Yong Wang、Xing‐Wang Wang
DOI:10.1002/adsc.202200875
日期:2022.12.20
phenyl(vinyl)sulfane. Several series of opticallyactive functionalized 3,4-dihydro-2H-pyran or ring fused dihydropyran derivatives were obtained in high yields with high diastereo- and enantioselectivity. The procedure was able to tolerate a relatively wide range of substrates. The coordination mode of chiral bis-oxalamide with Sc(III) was demonstrated by the X-ray crystallographic structure, and DFT calculations were
在温和的反应条件下,研究了手性双草酰胺(CBOA)/稀土金属配合物催化的不对称逆电子需求氧杂-杂-狄尔斯-阿尔德(HDA)反应,该反应在β,γ-不饱和α-之间进行酮酯和各种富电子亲二烯体,如环戊二烯、2,3-二氢呋喃、3,4-二氢-2H-吡喃、四氢吡啶以及苯基(乙烯基)硫烷。几个系列的旋光功能化3,4-二氢-2 H-吡喃或环稠合二氢吡喃衍生物以高产率和高非对映和对映选择性获得。该程序能够耐受相对广泛的底物。通过 X 射线晶体结构证明了手性双草酰胺与 Sc(III) 的配位模式,并进行了 DFT 计算以揭示区域和立体控制。