Abstract
Organic photoredox catalysts with a long excited-state lifetime have emerged as promising alternatives to transition-metal-complex photocatalysts. This paper explains the effectiveness of using long-lifetime photoredox catalysts for organic transformations, focusing on the structures and photophysics that enable long excited-state lifetimes. The electrochemical potentials of the reported organic, long-lifetime photocatalysts are compiled and compared with those of the representative Ir(III)- and Ru(II)-based catalysts. This paper closes by providing recent demonstrations of the synthetic utility of the organic catalysts.
1 Introduction
2 Molecular Structure and Photophysics
3 Photoredox Catalysis Performance
4 Catalysis Mediated by Long-Lifetime Organic Photocatalysts
4.1 Photoredox Catalytic Generation of a Radical Species and its Addition to Alkenes
4.2 Photoredox Catalytic Generation of a Radical Species and its Addition to Arenes
4.3 Photoredox Catalytic Generation of a Radical Species and its Addition to Imines
4.4 Photoredox Catalytic Generation of a Radical Species and its Addition to Substrates Having C≡X Bonds (X=C, N)
4.5 Photoredox Catalytic Generation of a Radical Species and its Bond Formation with Transition Metals
4.6 Miscellaneous Reactions of Radical Species Generated by Photoredox Catalysis
5 Conclusions
Key words
photoredox catalysis - organic photocatalysts - long lifetime - photoinduced electron transfer - organic transformations
