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(Thio)urea-Based Covalent Organic Framework as a Hydrogen-Bond-Donating Catalyst.

ABSTRACT: Two-dimensional urea- and thiourea-containing covalent organic frameworks (COFs) were synthesized at ambient conditions at large scale within 1 h in the absence of an acid catalyst. The site-isolated urea and thiourea in the COF showed enhanced catalytic efficiency as a hydrogen-bond-donating organocatalyst compared to the molecular counterparts in epoxide ring-opening reaction, aldehyde acetalization, and Friedel-Crafts reaction. The COF catalysts also had excellent recyclability.

SUBMITTER: Hu J

PROVIDER: S-EPMC7815320 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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(Thio)urea-Based Covalent Organic Framework as a Hydrogen-Bond-Donating Catalyst.

Hu Jiyun J Zanca Federica F Lambe Patricia P Tsuji Miu M Wijeweera Samantha S Todisco Stefano S Mastrorilli Piero P Shirley William W Benamara Mourad M Moghadam Peyman Z PZ Beyzavi Hudson H

ACS applied materials & interfaces 20200623 26

Two-dimensional urea- and thiourea-containing covalent organic frameworks (COFs) were synthesized at ambient conditions at large scale within 1 h in the absence of an acid catalyst. The site-isolated urea and thiourea in the COF showed enhanced catalytic efficiency as a hydrogen-bond-donating organocatalyst compared to the molecular counterparts in epoxide ring-opening reaction, aldehyde acetalization, and Friedel-Crafts reaction. The COF catalysts also had excellent recyclability. ...[more]

PMID: 32511903

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