Polyether functionalized cyclodextrin-based biomass organic catalyst and preparation method thereof

Abstract

The invention relates to a polyether functionalized cyclodextrin-based organic catalyst and a preparation method thereof, and provides a concept of function enhancement based on a hydrogen bond blocking mechanism by utilizing the characteristic of dynamic reversibility of hydrogen bonds in order to improve the problem of low effective utilization rate of traditional cyclodextrin and functionalized derivative catalysts thereof due to an intermolecular hydrogen bond network. A novel cyclodextrin-based organic catalyst with enhanced polyether organic alkali salt function is created by assembling a hydrogen bond blocking group'polyether functionalized organic alkali 'with high flexibility into molecules of cyclodextrin; a large number of ether bond oxygen atoms on a polyether chain are used as hydrogen bond receptors, so that the ether bond oxygen atoms and hydroxyl groups on the hydrophilic outer wall of cyclodextrin preferentially form intramolecular hydrogen bonds, thereby effectively blocking the formation of a cyclodextrin intermolecular hydrogen bond network and improving the effective utilization rate of the cyclodextrin-based organic catalyst; as an efficient organic catalyst, the polyether functionalized cyclodextrin can be applied to various organic synthesis reactions.

Description

technical field [0001] The invention relates to the technical field of chemistry and chemical engineering, in particular to a polyether functionalized cyclodextrin-based biomass organic catalyst and a preparation method thereof. Background technique [0002] Cyclodextrin (CD), mainly including α-CD, β-CD and γ-CD, has a unique outer hydrophilic / inner hydrophobic macrocyclic cavity structure and contains a large number of primary and secondary hydroxyl groups. Biomass-based organic catalysts have gained important applications in the fields of "supramolecular catalysis", "simulated enzyme catalysis" and "confined catalysis". However, due to the rigid truncated conical structure and dense intermolecular hydrogen bond network of CDs, they are only soluble in water and a few dipolar aprotic solvents such as DMF and DMSO, while in most commonly used organic solvents or The poor solubility in the catalytic reaction substrate greatly limits the application of CD in catalytic reacti...

AI Technical Summary

Problems solved by technology

However, due to the rigid truncated conical structure and dense intermolecular hydrogen bond network of CDs, they are only soluble in water and a few dipolar aprotic solvents such as DMF and DMSO, while in most commonly used organic solvents or The solubility in the catalytic reaction substrate is poor, which greatly limits the application of CD in catalytic reactions

[0003] In order to improve this situation, CD functionalized derivatives modified by various functional groups were successively synthesized (Chem. Rev. 1998, 98, 1977-1996.), but inefficient functionalization usually cannot effectively destroy the crystalline region of CD or block The formation of the hydrogen bond network of CD itself makes it difficult for CD derivatives to be dissolved by the substrate, forming heterogeneous catalysis

Although the molecules on the surface or looser regions of CD derivatives can participate in the catalytic reaction, a large number of molecules present in the crystalline region cannot be effectively utilized, resulting in a low effective utilization rate.

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