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Self-Assembled Bimetallic Aluminum-Salen Catalyst for the Cyclic Carbonates Synthesis.

ABSTRACT: Bimetallic bis-urea functionalized salen-aluminum catalysts have been developed for cyclic carbonate synthesis from epoxides and CO2. The urea moiety provides a bimetallic scaffold through hydrogen bonding, which expedites the cyclic carbonate formation reaction under mild reaction conditions. The turnover frequency (TOF) of the bis-urea salen Al catalyst is three times higher than that of a μ-oxo-bridged catalyst, and 13 times higher than that of a monomeric salen aluminum catalyst. The bimetallic reaction pathway is suggested based on urea additive studies and kinetic studies. Additionally, the X-ray crystal structure of a bis-urea salen Ni complex supports the self-assembly of the bis-urea salen metal complex through hydrogen bonding.

SUBMITTER: Seong W

PROVIDER: S-EPMC8271522 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Self-Assembled Bimetallic Aluminum-Salen Catalyst for the Cyclic Carbonates Synthesis.

Seong Wooyong W Hahm Hyungwoo H Kim Seyong S Park Jongwoo J Abboud Khalil A KA Hong Sukwon S

Molecules (Basel, Switzerland) 20210705 13

Bimetallic bis-urea functionalized salen-aluminum catalysts have been developed for cyclic carbonate synthesis from epoxides and CO2. The urea moiety provides a bimetallic scaffold through hydrogen bonding, which expedites the cyclic carbonate formation reaction under mild reaction conditions. The turnover frequency (TOF) of the bis-urea salen Al catalyst is three times higher than that of a μ-oxo-bridged catalyst, and 13 times higher than that of a monomeric salen aluminum catalyst. ...[more]

PMID: 34279436

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