By the Goldberg reaction

Amides may be converted to iV-alkyl and iV-acyl derivatives by appropriate condensation reagents. C-Alkylations of amides can also be carried out to modify the carbon skeleton of a compound. N-arylamides may be prepared by the Goldberg reaction of an amide with an aryl halide in the presence of potassium carbonate and cuprous iodide. 

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