Cobalt‐Catalyzed Formation of Functionalized Diarylmethanes from Benzylmesylates and Aryl Halides

Abstract

A simple cobalt‐catalyzed reductive coupling protocol allowing the synthesis of functionalized diarylmethanes from benzyl mesylate is described. The possibility to directly use the benzyl alcohol as a result of a two‐step reaction is also presented. This method tolerates a variety of functional groups. A benzyl radical is likely involved.magnified image

“Bulky-Yet-Flexible” α-Diimine Palladium-Catalyzed Reductive Heck Cross-Coupling: Highly Anti-Markovnikov-Selective Hydroarylation of Alkene in Air

“…1,2-Bis(4-chlorophenyl)ethane (5a). 55 The cross-coupling product compound was isolated by silica gel column chromatography using petroleum ether/ethyl acetate (50:1) as the eluent to afford a transparent crystal in 87% yield (217 mg). 1 H NMR (400 MHz, CDCl 3 ): δ 7.26−7.20 (m, 4H), 7.10−6.98 (m, 4H), 2.85 (s, 4H).…”

Dehalogenation and Desulfonation from Aryl and Alkyl Compounds with a Cobalt Catalyst in the Presence of Alcohol

“…The result of this study is presented below: aryl and alkyl bromides or chlorides were dehalogenated at room temperature in user‐friendly conditions with a good functional tolerance. As the cobalt‐catalyzed reduction of arylsulfone using a cobalt NHC complex in combination with alkylmagnesium reagents was recently described, [21] we also investigated the hydrodesulfonation of sulfonate compounds, which reacted already efficiently using cobalt catalysis [20a,22] …”

Zn-Mediated Hydrodeoxygenation of Tertiary Alkyl Oxalates

“…9a With DMA as the solvent, the use of Co salts to replace Ni as the promoter also generated 1 in 37% yield (entry 9), wherein the reaction efficiency is not high. 16 By contrast, copper salts were incompetent (entry 10). 17 Replacement of PBI with other pyridine-containing additives did not improve the results (entries 11-13).…”