中科院化学所王栋团队通过分子内Povarov反应构建稳定的铬烯喹啉共价有机框架。相关研究成果于2022年2月7日发表在《美国化学会杂志》。

化学稳定的铬烯喹啉（CQ）共价有机框架（COF）是由亚胺COFs的合成后转化而成。分子内Povarov反应的关键步骤是通过化学键将预先整合的炔基转化为亚胺键两侧的苯环，从而提供阶梯型CQ键。该新方法具有80–90%的高环化程度，这赋予CQ-COFs对强酸、强碱和氧化还原试剂具有优异的化学稳定性。

该合成方法可应用于具有不同对称性和功能核心部分的各种单体。CQ-COFs的吸收和荧光强度对酸敏感，能够对强酸性环境进行双模传感。

附：英文原文

Title: Constructing Stable Chromenoquinoline-Based Covalent Organic Frameworks via Intramolecular Povarov Reaction

Author: Xiao-Rui Ren, Bin Bai, Qingsong Zhang, Qing Hao, Yunlong Guo, Li-Jun Wan, Dong Wang

Issue&Volume: February 7, 2022

Abstract: Chemically stable chromenoquinoline (CQ)-based covalent organic frameworks (COFs) were constructed by postsynthetic conversion of imine COFs. The key step of an intramolecular Povarov reaction can transform a preintegrated alkyne group to bridge the benzene rings on both sides of the imine linkage via chemical bonds, affording a ladder-type CQ linkage. This novel approach achieves a high cyclization degree of 80–90%, which endows the CQ-COFs with excellent chemical stability toward strong acid, base, and redox reagents. The synthetic approach can be applied to various monomers with different symmetries and functional core moieties. The absorption and fluorescence intensities of CQ-COFs are sensitive to acid, which allows for dual-mode sensing of strongly acidic environments.

DOI: 10.1021/jacs.1c13005

Source: https://pubs.acs.org/doi/10.1021/jacs.1c13005