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DOI: 10.1055/a-1771-4883
A Photochemical Microfluidic Reactor for Photosensitized [2+2] Cycloadditions
Research in the Laraia Lab is supported by the Novo Nordisk Foundation (NNF21OC0067188), the Carlsberg Foundation (CF19-0072), and the Independent Research Fund Denmark (9041-00241B and 9041-00248B). K.Q. acknowledges the Carlsberg Foundation (CF18-0631) for financial support. M.N. acknowledges the Villum Foundation (19049) for financial support.
Abstract
Here we report a microfluidic system for photochemical cycloadditions fabricated using silicon micro processing technologies. The system was optimized to yield residence times of just a few minutes for a range of photochemical [2+2]-cycloaddition reactions facilitated using high power UV-LEDs at 375 nm and triplet photosensitizers, which removed the need for the low wavelengths typically required for these types of transformations. Adducts using different excitable olefins with different linear, carbocyclic, and heterocyclic coupling partners were explored to demonstrate the feasibility of performing photochemistry in microflow in an academic research environment. Finally, a reaction leading to a novel dihydrooxepin-2(3H)-one scaffold and a mechanistic proposal for its formation are reported.
Supporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/a-1771-4883.
- Supporting Information
Publication History
Received: 28 October 2021
Accepted after revision: 14 February 2022
Accepted Manuscript online:
14 February 2022
Article published online:
14 March 2022
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