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.

Alkyl chlorides and aryl chlorides are among the most abundant and stable carbon electrophiles. Although their coupling with carbon nucleophiles is well developed, the cross-electrophile coupling of aryl chlorides with alkyl chlorides has remained a challenge. We report here the first general approach to this transformation. The key to productive, selective crosscoupling is the use of a small amount of iodide or bromide along with a recently reported ligand, pyridine-2,6-bis(Ncyanocarboxamidine) (PyBCam CN ). The scope of the reaction is demonstrated with 35 examples (63 ± 16% average yield), and we show that the Br − and I − additives act as cocatalysts, generating a low, steady-state concentration of more-reactive alkyl bromide/ iodide.

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