The size complementarity between a host and a guest is a critical prerequisite for selective molecular recognition.Numerous artificial host systems have been designed to achieve size-selective recognition and chemical...The size complementarity between a host and a guest is a critical prerequisite for selective molecular recognition.Numerous artificial host systems have been designed to achieve size-selective recognition and chemical transformations.However,the inherent challenge lies in the fixed selectivity governed by a size-exclusion mechanism dictated by the host's structure.Modulating the selectivity necessitates structural modifications of hosts.Examples of host systems with modifiable sizeselectivity are rare.In this study,we present an approach to modulating guest-selectivity via endo-functionalization of supramolecular cavities.Heteroleptic Pd2A3B-cages are constructed with a Pd2A3precursor or directly from palladium ions and relevant ligands.Furthermore,the simultaneous and selective formation of multiple hetero-cages was achieved by simply mixing PdIIand the free ligands in a one-pot reaction.The fidelity of the assembly process relies on cooperative steric control at the periphery and within the cavity of the hetero-cages,respectively.The central steric group also functions as the endohedral moiety.Variations of the endohedral groups facilitate facile and modular derivatization of the microenvironment within the cages,enabling the fine-tuning of guest binding affinities as evidenced by titration experiments.This strategy offers a new solution for the development of customized host structures.展开更多
基金supported by the National Natural Science Foundation of China(22171192)the“1000-Youth Talents Program”,the Science&Technology Department of Sichuan Province(2022ZYD0050)the Fundamental Research Funds for the Central Universities。
文摘The size complementarity between a host and a guest is a critical prerequisite for selective molecular recognition.Numerous artificial host systems have been designed to achieve size-selective recognition and chemical transformations.However,the inherent challenge lies in the fixed selectivity governed by a size-exclusion mechanism dictated by the host's structure.Modulating the selectivity necessitates structural modifications of hosts.Examples of host systems with modifiable sizeselectivity are rare.In this study,we present an approach to modulating guest-selectivity via endo-functionalization of supramolecular cavities.Heteroleptic Pd2A3B-cages are constructed with a Pd2A3precursor or directly from palladium ions and relevant ligands.Furthermore,the simultaneous and selective formation of multiple hetero-cages was achieved by simply mixing PdIIand the free ligands in a one-pot reaction.The fidelity of the assembly process relies on cooperative steric control at the periphery and within the cavity of the hetero-cages,respectively.The central steric group also functions as the endohedral moiety.Variations of the endohedral groups facilitate facile and modular derivatization of the microenvironment within the cages,enabling the fine-tuning of guest binding affinities as evidenced by titration experiments.This strategy offers a new solution for the development of customized host structures.
