Visible-Light-Promoted, Catalyst-Free Gomberg–Bachmann Reaction: Synthesis of Biaryls
作者:Juyoung Lee、Boseok Hong、Anna Lee
DOI:10.1021/acs.joc.9b00557
日期:2019.7.19
Biaryls were synthesized via a novel visible-light-promoted Gomberg–Bachmann reaction that does not require a photosensitizer or any metal reagents. The formation of an electron donor–acceptor complex between aryl diazonium salts and pyridine allows, under visible-light irradiation, the synthesis of biaryls in moderate-to-high yields.
Abstract Palladium-catalysed Buchwald-Hartwig amination of ortho-substituted hindered aryl bromides or chlorides with 9H-carbazole has been investigated. In the amination of 1-bromo- or chloronaphthalene with 9H-carbazole, the combined use of Pd2(dba)3 as a Pd precursor, Buchwald ligands with two tert-butyl groups and LiOtBu or lithium hexamethyldisilazide as a base led to satisfactory yields. N,N’-Bis[2
The efficient production of 9-(2-substituted phenyl)-9H-carbazole is achieved by reacting 9H-carbazole derivative with 2-substituted-1-halobenzene in the presence of a palladium compound, an imidazolidene compound represented by formula (4) [Chemical formula 1], and a lithium base.
Shedding UV‐Light on Mechanochemistry: The Regioselective Solid‐State Photochemical Synthesis of Nanographenes
作者:Daniel M. Baier、Carolina Spula、Stephen Fanenstich、Sven Grätz、Lars Borchardt
DOI:10.1002/anie.202218719
日期:——
Photochemistry and mechanochemistry have been combined to synthesize nanographenes in the complete absence of bulk solvents. The concept is showcased with two reactions—the Mallory reaction and the cyclodehydrochlorination, both applicable to the intramolecular formation of C−C bonds. Moreover, the approach can even form these bonds regioselectively in larger systems—something not possible before in