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Tuning catalysis of boronic acids in microgels by in situ reversible structural variations.

ABSTRACT: The catalysis of boronic acids immobilized in polymer microgels can be modulated by bubbling with N₂/CO₂ gas, and in some cases by adding glucose, making their catalytic activity comparable or even superior to that of the corresponding free boronic acid monomers homogeneously dispersed in solutions and, more importantly, making these boronic-acid-containing polymer microgels able to catalyze alternate reactions that may extend the usefulness. This enhanced catalytic function of these boronic-acid-containing microgels as organoboron acid catalysts is plausibly achieved via in situ reversibly structural variations. Kinetic studies have been carried out on the model boronic-acid-catalyzed aza-Michael addition, aldol, amidation, and [4 + 2] cycloaddition reactions in order to better understand the catalytic process.

SUBMITTER: Zhai Z

PROVIDER: S-EPMC9048991 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Tuning catalysis of boronic acids in microgels by in situ reversible structural variations.

Zhai Zhenghao Z Du Xue X Wu Qingshi Q Zhu Lin L Farooqi Zahoor H ZH Li Jin J Lan Ruyue R Wang Yusong Y Wu Weitai W

RSC advances 20200122 7

The catalysis of boronic acids immobilized in polymer microgels can be modulated by bubbling with N2/CO2 gas, and in some cases by adding glucose, making their catalytic activity comparable or even superior to that of the corresponding free boronic acid monomers homogeneously dispersed in solutions and, more importantly, making these boronic-acid-containing polymer microgels able to catalyze alternate reactions that may extend the usefulness. This enhanced catalytic functio ...[more]

PMID: 35492625

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