Decarboxylative Cross-Electrophile Coupling of N-Hydroxyphthalimide Esters with Aryl Iodides

Huihui, K., J. Caputo, Z. Melchor, A. Olivares, A. Spiewak, K. Johnson, T. DiBenedetto, S. Kim, L. Ackerman, and D. Weix. Decarboxylative Cross-Electrophile Coupling of N-Hydroxyphthalimide Esters With Aryl Iodides. J. Am. Chem. Soc., 5019.
Abstract A new method for the decarboxylative coupling of alkyl N-hydroxyphthalimide esters (NHP esters) with aryl iodides is presented. In contrast to previous studies that form alkyl radicals from carboxylic acid derivatives, no photocatalyst, light, or arylmetal reagent is needed, only nickel and a reducing agent (Zn). Methyl, primary, and secondary alkyl groups can all be coupled in good yield (77% ave yield). One coupling with an acid chloride is also presented. Stoichiometric reactions of (dtbbpy)Ni(2-tolyl)I with an NHP ester show for the first time that arylnickel(II) complexes can directly react with NHP esters to form alkylated arenes.
Keywords acid-chloridesalkyl-halidesbromidesco-catalysisketone formationmerging photoredoxnickel catalysisquaternary carbonstransfer mechanismvisible-light photocatalysis
DOI 10.1021/jacs.6b01533