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Metal-salen molecular cages as efficient and recyclable heterogeneous catalysts for cycloaddition of CO₂ with epoxides under ambient conditions.

ABSTRACT: A salen based molecular cage, salen@cage, was synthesized and complexed with Co and Al to yield metal-salen molecular cages, Co(ii)@cage, Co(iii)@cage and Al(iii)@cage. These cages were demonstrated to be efficient heterogeneous catalysts for the cycloaddition of CO₂ with styrene oxide, achieving full conversion at 25 °C and 1 atm CO₂. Good to excellent yields of various cyclic carbonates were also achieved under mild conditions. Al(iii)@cage can be reused up to five times without any significant loss of its high catalytic activity. The capability to access a variety of heterogeneous organometallic catalysts with salen@cage offers new prospects for practical CO₂ utilization and chemical manufacturing.

SUBMITTER: Ng CK

PROVIDER: S-EPMC6357855 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Metal-salen molecular cages as efficient and recyclable heterogeneous catalysts for cycloaddition of CO2 with epoxides under ambient conditions.

Ng Chee Koon CK Toh Ren Wei RW Lin Ting Ting TT Luo He-Kuan HK Hor T S Andy TSA Wu Jie J

Chemical science 20181129 5

A salen based molecular cage, salen@cage, was synthesized and complexed with Co and Al to yield metal-salen molecular cages, Co(ii)@cage, Co(iii)@cage and Al(iii)@cage. These cages were demonstrated to be efficient heterogeneous catalysts for the cycloaddition of CO2 with styrene oxide, achieving full conversion at 25 °C and 1 atm CO2. Good to excellent yields of various cyclic carbonates were also achieved under mild conditions. Al(iii)@cage can be reused up to five times ...[more]

PMID: 30809373

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