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Self-Assembly and Cascade Catalysis by a Soft-Oxometalate (SOM) System.

ABSTRACT: Cascade catalysis has gained importance due to its various applications. In this work, cascade catalysis was performed using a self-assembled soft-oxometalate (SOM) as a model system. At first, we synthesized an oxometalate (OM) hybrid with a polymerizable organic cation, namely tetrakis(4-aminophenyl)methane, and an OM, K₈[SiW₁₁O₃₉]. The hybrid in turn was converted into SOM in water, DMSO mixture, and characterized by different techniques, ranging from electron microscopy to DLS. The SOM state is endowed with the ability to polymerize the aniline based counter ions associated with it in the presence of UV-light. This polymerization is possible due to the presence of photocatalytic OMs (oxometalates) in the SOMs. The polymer-SOM hybrid in cascade oxidizes selectively aniline to nitrobenzene and nitrite to nitrate owing to the residual oxidizing property of the OM constituents in it. This is the first example of cascade catalysis in SOM chemistry.

SUBMITTER: Das K

PROVIDER: S-EPMC7729020 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Self-Assembly and Cascade Catalysis by a Soft-Oxometalate (SOM) System.

Das Kousik K Yan Tingting T Paul Shounik S Qiu Shilun S Ben Teng T Roy Soumyajit S

Frontiers in chemistry 20201127

Cascade catalysis has gained importance due to its various applications. In this work, cascade catalysis was performed using a self-assembled soft-oxometalate (SOM) as a model system. At first, we synthesized an oxometalate (OM) hybrid with a polymerizable organic cation, namely tetrakis(4-aminophenyl)methane, and an OM, K8[SiW11O39]. The hybrid in turn was converted into SOM in water, DMSO mixture, and characterized by different techniques, ranging from electron ...[more]

PMID: 33330395

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