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Abstract Visible‐light photocatalysis has advanced as a versatile tool in organic synthesis. However, attaining precise stereocontrol in photocatalytic reactions has been a longstanding challenge due to undesired photochemical background reactions and the involvement of highly reactive radicals or radical ion intermediates generated under photocatalytic conditions. To address this problem and expand the synthetic utility of photocatalytic reactions, a number of innovative strategies, including mono‐ and dual‐catalytic approaches, have recently emerged. Of these, exploiting chiral organocatalysis, such as enamine catalysis, iminium‐ion catalysis, Brønsted acid/base catalysis, andN‐heterocyclic carbene catalysis, to induce chirality transfer of photocatalytic reactions has been widely explored. This Review aims to provide a current, comprehensive overview of asymmetric photocatalytic reactions enabled by chiral organocatalysts published through June 2021. The substrate scope, advantages, limitations, and proposed reaction mechanisms of each reaction are discussed. This review should serve as a reference for the development of visible‐light‐induced asymmetric photocatalysis and promote the improvement of the chemical reactivity and stereoselectivity of these reactions.
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Strategic Use of Visible-Light Photoredox Catalysis in Natural Product Synthesis
Recent progress in the development of photocatalytic reactions promoted by 5 visible light is leading to a renaissance in the use of photochemistry in the construction of 6 structurally elaborate organic molecules. Because of the rich functionality found in natural 7 products, studies in natural product total synthesis provide useful insights into functional 8 group compatibility of these new photocatalytic methods as well as their impact on synthetic 9 strategy. In this review, we examine total syntheses published through the end of 2020 that 10 employ a visible-light photoredox catalytic step. To assist someone interested in employing 11 the photocatalytic steps discussed, the review is organized largely by the nature of the bond 12 formed in the photocatalytic step.
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- Award ID(s):
- 1661612
- PAR ID:
- 10274892
- Date Published:
- Journal Name:
- Chemical Reviews
- ISSN:
- 0009-2665
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acs.chemrev.1c00247
