Following GENERAL METHOD 6-1 for SNAr, Intermediate 2-1 (50 mg, 0.174 mmol), tert-butyl piperazine-1-carboxylate (59 mg, 0.314 mmol), DIPEA (0.06 mL, 0.349 mmol), and n-butanol (0.1 mL) were combined in a 4 mL reaction vial and heated at 120° C. overnight. The reaction was cooled to RT and EtOAc was added. The white solid that formed was filtered off and washed with EtOAc, dissolved in DCM and washed with H2O. The organic layer was dried with sodium sulfate, filtered, and concentrated in vacuo to afford the desired product.
