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Continuous Flow Approach for Benzylic Photo-oxidations Using Compressed Air.

ABSTRACT: A continuous flow approach for the aerobic photo-oxidation of benzylic substrates to ketone and aldehyde products is presented. The resulting process exploits UV-A LEDs (375 nm) in combination with a Corning AFR reactor that ensures effective gas-liquid mixing and leads to short residence times of 1 min. A variety of benzylic substrates are converted to their corresponding carbonyl products, and scalability is demonstrated to produce multigram quantities of products within a few hours. Overall, this continuous flow approach offers several improvements over alternative oxidation methods due to the combined use of air as an oxidant and SAS (sodium anthraquinone-2 sulfonate) as a water-soluble photocatalyst. The use of greener and safer conditions together with process intensification principles renders this flow approach attractive for further industrial applications.

SUBMITTER: Bannon R

PROVIDER: S-EPMC11334174 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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Continuous Flow Approach for Benzylic Photo-oxidations Using Compressed Air.

Bannon Ruairi R Morrison Gary G Smyth Megan M Moody Thomas S TS Wharry Scott S Roth Philippe M C PMC Gauron Guillaume G Baumann Marcus M

Organic process research & development 20240724 8

A continuous flow approach for the aerobic photo-oxidation of benzylic substrates to ketone and aldehyde products is presented. The resulting process exploits UV-A LEDs (375 nm) in combination with a Corning AFR reactor that ensures effective gas-liquid mixing and leads to short residence times of 1 min. A variety of benzylic substrates are converted to their corresponding carbonyl products, and scalability is demonstrated to produce multigram quantities of products within a few hours. Overall, ...[more]

PMID: 39171129

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