Exclusive photodimerization reactions of chromone-2-carboxylic esters depending on reaction media.

Org Lett

Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, Chiba University, Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.

Published: October 2010

AI Article Synopsis

  • The irradiation of chromone-2-carboxylic esters leads to the selective creation of C(2) chiral anti-HH dimers when exposed to light in the triplet excited state.
  • When the same compounds are exposed to light in solid-state conditions, they produce anti-HT dimers.
  • The formation of these dimers in solid-state is influenced by the arrangement of molecules within the crystal structure.

Article Abstract

The irradiation of chromone-2-carboxylic esters resulted in the stereo- and regioselective formation of C(2) chiral anti-HH dimers from the triplet excited state. On the contrary, photolysis in the solid-state gave anti-HT dimers exclusively controlled by molecular arrangement in the crystal.

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http://dx.doi.org/10.1021/ol101734kDOI Listing

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Exclusive photodimerization reactions of chromone-2-carboxylic esters depending on reaction media.

Org Lett

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Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, Chiba University, Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.

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  • When the same compounds are exposed to light in solid-state conditions, they produce anti-HT dimers.
  • The formation of these dimers in solid-state is influenced by the arrangement of molecules within the crystal structure.
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