Photochemical Nickel-Catalyzed C–H Arylation: Synthetic Scope and Mechanistic Investigations
Autor: | John C. Tellis, Drew R. Heitz, Gary A. Molander |
---|---|
Rok vydání: | 2016 |
Předmět: |
Bromine
010405 organic chemistry Communication Aryl chemistry.chemical_element General Chemistry 010402 general chemistry Photochemistry 7. Clean energy 01 natural sciences Biochemistry Catalysis 0104 chemical sciences Homolysis chemistry.chemical_compound Nickel Colloid and Surface Chemistry chemistry Photocatalysis Iridium Visible spectrum |
Zdroj: | Journal of the American Chemical Society |
ISSN: | 1520-5126 0002-7863 |
Popis: | An iridium photocatalyst and visible light facilitate a room temperature, nickel-catalyzed coupling of (hetero)aryl bromides with activated α-heterosubstituted or benzylic C(sp3)–H bonds. Mechanistic investigations on this unprecedented transformation have uncovered the possibility of an unexpected mechanism hypothesized to involve a Ni–Br homolysis event from an excited-state nickel complex. The resultant bromine radical is thought to abstract weak C(sp3)–H bonds to generate reactive alkyl radicals that can be engaged in Ni-catalyzed arylation. Evidence suggests that the iridium photocatalyst facilitates nickel excitation and bromine radical generation via triplet–triplet energy transfer. |
Databáze: | OpenAIRE |
Externí odkaz: |