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2,5-Dimethylphenacyl esters: A photoremovable protecting group for phosphates and sulfonic acids

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Abstract

2,5-Dimethylphenacyl phosphoric and sulfonic esters release the corresponding acids upon irradiation in nearly quantitative isolated yields, with quantum yields Φ = 0.71 and 0.68 in methanol, 0.09 and 0.19 in benzene. In methanol solution the reactions proceed predominantly via the (Z)-photoenol, the lifetimes of which (20 and 25 μs) were determined by laser flash photolysis. The chromophore is proposed as an excellent photoremovable protecting group for use in organic synthesis and biochemistry.

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Acknowledgements

We gratefully acknowledge financial support from the Czech Ministry of Education, Youth and Sport (CEZ: J07/ 98:143100005) and the Swiss National Science Foundation (Project No. 20-61746.00).

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Authors and Affiliations

  1. Department of Organic Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ - 611 37, Brno, Czech Republic

    Petr Klán & Tomáš Pospíšil

  2. Departement Chemie der Universität Basel, Klingelbergstrasse 80, CH-4056, Basel, Switzerland

    Anna Paola Pelliccioli & Jakob Wirz

Authors
  1. Petr Klán
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  2. Anna Paola Pelliccioli
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  3. Tomáš Pospíšil
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  4. Jakob Wirz
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Correspondence to Petr Klán or Jakob Wirz.

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Klán, P., Pelliccioli, A.P., Pospíšil, T. et al. 2,5-Dimethylphenacyl esters: A photoremovable protecting group for phosphates and sulfonic acids. Photochem Photobiol Sci 1, 920–923 (2002). https://doi.org/10.1039/B208171G

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