Jump to main content
Jump to site search

Issue 20, 2019
Previous Article Next Article

Chiral salen Cr(iii) complexes encapsulated in thermo-responsive polymer nanoreactors for asymmetric epoxidation of alkenes in water

Author affiliations

Abstract

Chiral salen Cr(III) (Cr(salen)) complexes were encapsulated in thermo-responsive polymer nanoreactors through folding an amphiphilic random copolymer of poly(N-isopropylacrylamide-co-IL/Cr(salen)) (poly(NIPAAM-co-IL/Cr(salen)) around Cr(salen) in water. The resulting catalytic nanoreactors exhibited several advantages over the traditional Cr(salen) system for asymmetric epoxidation of alkenes in water. First, they were dispersed in water, behaving as a quasi-homogeneous catalyst for the aqueous asymmetric epoxidation. Second, they effectively sequestered substrates from the surrounding environment, creating a highly concentrated environment for efficient catalysis. Third, water was excluded from the nanoreactor, minimizing the undesired hydrolysis of epoxides. As a result, the compartmentalized catalysts mediated aqueous asymmetric epoxidation with unprecedented yields (92–95%) and enantioselectivities (ee, 92–99%), whereas the traditional Cr(salen) catalyst was far less efficient (4–12% yield and 29–44% ee). Moreover, the catalytic nanoreactor could be facilely recovered for reuse by thermo-controlled separation. This work highlighted the potential of using folded polymers as a platform for developing highly efficient catalytic nanoreactors for a number of important organic transformations in water.

Graphical abstract: Chiral salen Cr(iii) complexes encapsulated in thermo-responsive polymer nanoreactors for asymmetric epoxidation of alkenes in water

Back to tab navigation

Supplementary files

Publication details

The article was received on 15 Jul 2019, accepted on 03 Sep 2019 and first published on 04 Sep 2019


Article type: Paper
DOI: 10.1039/C9CY01398A
Catal. Sci. Technol., 2019,9, 5626-5635

  •   Request permissions

    Chiral salen Cr(III) complexes encapsulated in thermo-responsive polymer nanoreactors for asymmetric epoxidation of alkenes in water

    W. Wang, C. Li, Y. Pi, J. Wang, R. Tan and D. Yin, Catal. Sci. Technol., 2019, 9, 5626
    DOI: 10.1039/C9CY01398A

Search articles by author

Spotlight

Advertisements