The precise synthesis of planar chiral pillar[n]arenes(PAs)faces significant challenges due to their inherent dynamic racemization induced by rapid molecular flipping.To address this issue and enhance conformational s...The precise synthesis of planar chiral pillar[n]arenes(PAs)faces significant challenges due to their inherent dynamic racemization induced by rapid molecular flipping.To address this issue and enhance conformational stability of these macrocycles,we have developed a strategic approach involving the introduction of sterically bulky aryl(sp^(2))substituents at the molecular rims through dynamic kinetic resolution(DKR).A series of robust and chirality-aligned homo-and hetero-diaryl PAs(n=5,6)were achieved with excellent enantioselectivity(>95%ee)via Pd-catalyzed asymmetric Suzuki–Miyaura coupling reactions.Mechanism study revealed axial steric hindrance,rather than radial substitution,governs conformational chirality-locking in pillar[n]arenes.This work not only provides an attractive protocol for the enantioselective synthesis of planar chiral pillar[n]arenes,but also enriches the library of macrocycles for promising applications in chiral molecular machines,enantioselective sensors,and chiral luminescent materials.展开更多
The dyotropic rearrangement of β-lactones is a neglected treasure in the family of multi-bond reactions and pericyclic reactions.Despite its appealing synthetic potential,the complicated migration selectivity greatly...The dyotropic rearrangement of β-lactones is a neglected treasure in the family of multi-bond reactions and pericyclic reactions.Despite its appealing synthetic potential,the complicated migration selectivity greatly limits its widespread application.In this work,we report the first systematic and comprehensive computational study on the dyotropic rearrangements of β-lactones.The use of the double-hybrid functional ensures the accuracy of results.On the basis of the present study and our previous work,five methods to control the reaction selectivity of dyotropic rearrangements of β-lactones have been summarized,providing valuable references for synthetic chemists to design and develop brand-new type dyotropic reactions.展开更多
基金financial support from the Natural Science Foundation of Ningxia(Nos.2024AAC03023 and 2024AAC03024)。
文摘The precise synthesis of planar chiral pillar[n]arenes(PAs)faces significant challenges due to their inherent dynamic racemization induced by rapid molecular flipping.To address this issue and enhance conformational stability of these macrocycles,we have developed a strategic approach involving the introduction of sterically bulky aryl(sp^(2))substituents at the molecular rims through dynamic kinetic resolution(DKR).A series of robust and chirality-aligned homo-and hetero-diaryl PAs(n=5,6)were achieved with excellent enantioselectivity(>95%ee)via Pd-catalyzed asymmetric Suzuki–Miyaura coupling reactions.Mechanism study revealed axial steric hindrance,rather than radial substitution,governs conformational chirality-locking in pillar[n]arenes.This work not only provides an attractive protocol for the enantioselective synthesis of planar chiral pillar[n]arenes,but also enriches the library of macrocycles for promising applications in chiral molecular machines,enantioselective sensors,and chiral luminescent materials.
基金the financial support from the National Natural Science Foundation of China(21772109 and 21971140)the Beijing Natural Science Foundation(M21011)the Tsinghua-Peking University Center for Life Sciences(No.61020100120).
文摘The dyotropic rearrangement of β-lactones is a neglected treasure in the family of multi-bond reactions and pericyclic reactions.Despite its appealing synthetic potential,the complicated migration selectivity greatly limits its widespread application.In this work,we report the first systematic and comprehensive computational study on the dyotropic rearrangements of β-lactones.The use of the double-hybrid functional ensures the accuracy of results.On the basis of the present study and our previous work,five methods to control the reaction selectivity of dyotropic rearrangements of β-lactones have been summarized,providing valuable references for synthetic chemists to design and develop brand-new type dyotropic reactions.
