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Title: Getting excited about cycloadditions
Synthetic chemists use photochemistry to achieve challenging or unusual chemical transformations, but not all compounds are photoactive. Photosensitization is a process by which a molecule that is incapable of efficiently absorbing a particular wavelength of light directly is promoted to its triplet excited state (T 1 ) by an intermolecular triplet energy transfer from a photosensitizer, which is a compound that ideally has a large extinction coefficient, rapid rate of intersystem crossing, and a long-lived T 1 . A particular advantage of photosensitization is that distinctive reactivity profiles not accessible through ground states become facile from corresponding excited states ( 1 ). The use of photosensitizers in chemical synthesis has paralleled the rise in popularity and use of various photoredox catalysts ( 2 ). On page 1338 of this issue, Ma et al. ( 3 ) report a photosensitized dearomative [4 + 2] cycloaddition that converts simple, unsaturated building blocks into products of increased molecular complexity using visible light.  more » « less
Award ID(s):
1945463
PAR ID:
10336975
Author(s) / Creator(s):
Date Published:
Journal Name:
Science
Volume:
371
Issue:
6536
ISSN:
0036-8075
Page Range / eLocation ID:
1313 to 1313
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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