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Abstract Chemical modification is a powerful strategy for tuning the electronic properties of 2D semiconductors. Here we report the electrophilic trifluoromethylation of 2D WSe2and MoS2under mild conditions using the reagent trifluoromethyl thianthrenium triflate (TTT). Chemical characterization and density functional theory calculations reveal that the trifluoromethyl groups bind covalently to surface chalcogen atoms as well as oxygen substitution sites. Trifluoromethylation induces p‐type doping in the underlying 2D material, enabling the modulation of charge transport and optical emission properties in WSe2. This work introduces a versatile and efficient method for tailoring the optical and electronic properties of 2D transition metal dichalcogenides.
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Metal Ion‐Induced Large Fragment Deactivation: A Different Strategy for Site‐Selectivity in a Complex Molecule
Abstract Complex natural product functionalizations generally involve the use of highly engineered reagents, catalysts, or enzymes to react exclusively at a desired site through lowering of a select transition state energy. In this communication, we report a new, complementary strategy in which all transition states representing undesirable sites in a complex ionophore substrate are simultaneously energetically increased through the chelation of a metal ion to the large fragment we wish to neutralize. In the case of an electrophilic, radical based fluorination reaction, charge repulsion (electric field effects), induced steric effects, and electron withdrawal provide the necessary deactivation and proof of principle to afford a highly desirable natural product derivative. We envisage that many other electrophilic or charge based synthetic methods may be amenable to this approach as well.
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- Award ID(s):
- 2102116
- PAR ID:
- 10540782
- Editor(s):
- Tobey, Suzanne
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 63
- Issue:
- 13
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/anie.202317070
