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Radical couplings of cyanopyridine radical anions represent a valuable technology for functionalizing pyridines, which are prevalent throughout pharmaceuticals, agrochemicals, and materials. Installing the cyano group, which facilitates the necessary radical anion formation and stabilization, is challenging and limits the use of this chemistry to simple cyanopyridines. We discovered that pyridylphosphonium salts, installed directly and regioselectively from C–H precursors, are useful alternatives to cyanopyridines in radical–radical coupling reactions, expanding the scope of this reaction manifold to complex pyridines. Methods for both alkylation and amination of pyridines mediated by photoredox catalysis are described. Additionally, we demonstrate late-stage functionalization of pharmaceuticals, highlighting an advantage of pyridylphosphonium salts over cyanopyridines.
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From radical to triradical thin film processes: the Blatter radical derivatives
We demonstrate the possibility to evaporate Blatter radical derivatives in a controlled environment obtaining thin films that preserve the (poly)radical magnetic character. However, their thermal evaporation is challenging. We analyse the evaporation process and the thin film formation using thermodynamic concepts and describe the material properties also using first principles calculations. The presence of more than one radical site makes the radical more reactive, narrowing the windows left for evaporation, thus, favouring the assembly of molecules and island formation rather than two-dimensional growth.
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- PAR ID:
- 10319276
- Date Published:
- Journal Name:
- Journal of Materials Chemistry C
- Volume:
- 9
- Issue:
- 33
- ISSN:
- 2050-7526
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D1TC01541A
