Abstract
Since their discovery in 1970s, Katritzky salts have emerged as one of the most important classes of building blocks for use in organic synthesis and drug discovery. These bulky pyridinium salts derived from alkylamine can readily generate alkyl radical and undergo a variety of organic transformation reactions such as alkylation, arylation, alkenylation, alkynylation, carbonylation, sulfonylation, and borylation. Through these transformations, complexed molecules bearing new C–C, C–B, or C–S bonds can be constructed in easy ways and in simple steps. This review aims to summarize recent advances in these versatile building blocks in well-classified categories. Representative examples and their reaction mechanisms are discussed. The hope is to provide the scientific community with convenient access to collective information and accelerate further research.
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Abbreviations
- CSA:
-
Camphorsulfonic acid
- DABCO:
-
1,4-Diazabicyclo[2,2,2]octane
- DBU:
-
1,8-Diazabicyclo[5,4,0]undec-7-ene
- DET:
-
Density functional theory
- DMA:
-
N,N-Dimethylacetamide
- dOMebpy:
-
4,4′-Dimethoxy-2,2′-bipyridine
- dtbpy:
-
4,4′-Di-tert-butyl-2,2′-bipyridine
- ET:
-
Electron transfer
- Et3N:
-
Trimethylamine
- HAT:
-
Hydrogen-atom transfer
- PC:
-
Photocatalyst
- PET:
-
Photoinduced electron transfer
- SET:
-
Single-electron transfer
- SER:
-
Single-electron reductant
- SO2 :
-
Sulfur dioxide
- TEA:
-
Trimethylamine
- TEMPO:
-
2,2,6,6-Tetramethylpiperidine-1-oxyl
- terpy:
-
Terpyridine
- THIQs:
-
Tetrahydroisoquinolines
- MIDA:
-
Methyliminodiacetic acid
- NHC:
-
N-Heterocyclic carbene
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Acknowledgements
This work was supported by the National Natural Science Foundation of China (82073686, 81730108, and 81973635), the Scientific Research Foundation for Scholars of Hangzhou Normal University (2021QDL042, 2019QDL003), the Ministry of Science and Technology of China (High-end foreign experts program, G20200217005 and G2021017004), the Hangzhou City “115” plan to introduce overseas intelligence projects (20200215 and 20210120), and the Hangzhou Normal University School of Medicine Teaching Reform Fund (4125b30100112).
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Gao, Y., Jiang, S., Mao, ND. et al. Recent Progress in Fragmentation of Katritzky Salts Enabling Formation of C–C, C–B, and C–S Bonds. Top Curr Chem (Z) 380, 25 (2022). https://doi.org/10.1007/s41061-022-00381-x
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DOI: https://doi.org/10.1007/s41061-022-00381-x