Excited radical anions and excited anions in visible light photoredox catalysis

2019 ◽  
Vol 4 (12) ◽  
Author(s):  
Indrajit Ghosh

Abstract Over the last decade, visible light photocatalysis has dramatically increased the arsenal of methods for organic synthesis and changed the way we activate molecules for chemical reactions. Polypyridyl transition metal complexes, redox-active organic dyes, and inorganic semiconductors are typically used as photocatalysts for such transformations. This chapter reviews the applications of radical anions and anions as photosensitizers in visible light photoredox catalysis.

2020 ◽  
Vol 07 ◽  
Author(s):  
Avik K. Bagdi ◽  
Papiya Sikdar

Abstract:: Organic synthesis under environment friendly conditions has great impact in the sustainable development. In this context, visible light photocatalysis has emerged as a green model as this offers an energy-efficient pathway towards the organic transformation. Different transition-metal catalysts (Ir-, Ru-, Cu- etc) and organic dyes (eosin Y, rose bengal, methylene blue etc) are well-known photocatalysts in organic synthesis. Apart from the well-known organophotoredox catalysts, rhodamines (Rhodamine B and Rhodamine 6G) have been also employed as efficient photocatalysts for different organic transformations. In this review, we will focus on the photocatalysis by rhodamines in organic synthesis. Mechanistic pathway of the methodologies will also be discussed. We believe this review will stimulate the employment of rhodamines in the visible light photocatalysis for efficient organic transformations in the future.


Author(s):  
Vishal Srivastava ◽  
Pravin Kumar Singh ◽  
Shraddha Tivari ◽  
Praveen Pratap Singh

Visible light and photoredox catalysis have emerged as a powerful and long-lasting tool for organic synthesis, demonstrating the importance of a variety of chemical bond formation methods. Natural products, physiologically...


Synthesis ◽  
2019 ◽  
Vol 51 (16) ◽  
pp. 3021-3054 ◽  
Author(s):  
Yi Wei ◽  
Quan-Quan Zhou ◽  
Fen Tan ◽  
Liang-Qiu Lu ◽  
Wen-Jing Xiao

Visible-light-driven organic photochemical reactions have attracted substantial attention from the synthetic community. Typically, catalytic quantities of photosensitizers, such as transition metal complexes, organic dyes, or inorganic semiconductors, are necessary to absorb visible light and trigger subsequent organic transformations. Recently, in contrast to these photocatalytic processes, a variety of photocatalyst-free organic photochemical transformations have been exploited for the efficient formation of carbon–carbon and carbon–heteroatom bonds. In addition to not requiring additional photocatalysts, they employ low-energy visible light irradiation, have mild reaction conditions, and enable broad substrate diversity and functional group tolerance. This review will focus on a summary of representative work in this field in terms of different photoexcitation modes.1 Introduction2 Visible Light Photoexcitation of a Single Substrate3 Visible Light Photoexcitation of Reaction Intermediates4 Visible Light Photoexcitation of EDA Complexes between Substrates5 Visible Light Photoexcitation of EDA Complexes between Substrates and Reaction Intermediates6 Visible Light Photoexcitation of Products7 Conclusion and Outlook


2013 ◽  
Vol 113 (7) ◽  
pp. 5322-5363 ◽  
Author(s):  
Christopher K. Prier ◽  
Danica A. Rankic ◽  
David W. C. MacMillan

Science ◽  
2019 ◽  
Vol 364 (6439) ◽  
pp. eaav9713 ◽  
Author(s):  
Asik Hossain ◽  
Aditya Bhattacharyya ◽  
Oliver Reiser

Visible-light photoredox catalysis offers a distinct activation mode complementary to thermal transition metal catalyzed reactions. The vast majority of photoredox processes capitalizes on precious metal ruthenium(II) or iridium(III) complexes that serve as single-electron reductants or oxidants in their photoexcited states. As a low-cost alternative, organic dyes are also frequently used but in general suffer from lower photostability. Copper-based photocatalysts are rapidly emerging, offering not only economic and ecological advantages but also otherwise inaccessible inner-sphere mechanisms, which have been successfully applied to challenging transformations. Moreover, the combination of conventional photocatalysts with copper(I) or copper(II) salts has emerged as an efficient dual catalytic system for cross-coupling reactions.


2017 ◽  
Vol 4 (7) ◽  
pp. 1331-1335 ◽  
Author(s):  
Shi-Ming Xu ◽  
Jian-Qiang Chen ◽  
Dan Liu ◽  
Yun Bao ◽  
Yong-Min Liang ◽  
...  

Abundant and inexpensive aroyl chlorides have been employed for the first time as novel acyl radical precursors in visible-light photocatalysis.


Sign in / Sign up

Export Citation Format

Share Document