To a 5 mL glass microwave tube containing N-tert-butyl-5-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-tosyl-1H-indol-5-yl)-1,3,4-oxadiazol-2-amine (357.8 mg, 0.667 mmol) was added 2-bromo-4-cyclopropylpyrimidine (153 mg, 0.767 mmol) (CombiPhos Catalysts Inc.), potassium phosphate (425 mg, 2.001 mmol) (Sigma-Aldrich), dicyclohexyl(2′,4′,6′-triisopropylbiphenyl-2-yl)phosphine (19.08 mg, 0.040 mmol) (Strem), and Pd2(dba)3 (18.32 mg, 0.020 mmol) (Strem). The tube was purged with argon, the solids were treated with Dioxane (3.0 mL) and Water (0.300 mL), the tube was sealed, and the contents were heated in an Initiator microwave reactor (Personal Chemistry, Biotage AB, Inc., Upssala, Sweden) at 120° C. for 20 min. The mixture was treated with H2O and extracted with EtOAc. The organic layer was washed with brine, dried over MgSO4, filtered and concentrated. The crude material was purified by flash chromatography (eluting with 5-60% EtOAc in Hex) affording N-tert-butyl-5-(3-(4-cyclopropylpyrimidin-2-yl)-1-tosyl-1H-indol-5-yl)-1,3,4-oxadiazol-2-amine (86.2 mg, 0.163 mmol, 24.45) as an off-white foam. MS (ESI, pos. ion) m/z: 529.0 (M+1).
