Highly efficient continuous flow reactions using singlet oxygen as a "green" reagent.

Described is a new method for the efficient in situ production of singlet oxygen in a simple continuous flow photochemical reactor. The extremely large interfacial area generated by running the biphasic mixture in a narrow channel at a high flow rate ensures high throughput as well as fast and efficient oxidation of various alkenes, 1,3-dienes, and thioethers on a preparative scale.

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