Potassium Phosphate, Tribasic → N-tert-butyl-5-(3-(4-ethyl-5-fluoropyrimidin-2-yl)-1-tosyl-1H-indol-5-yl)-1,3,4-oxadiazol-2-amine

Participants

Reaction Conditions

Reaction Steps

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 (166 mg, 0.309 mmol) was added 2-chloro-4-ethyl-5-fluoropyrimidine (78 mg, 0.402 mmol), potassium phosphate (197 mg, 0.928 mmol), dicyclohexyl(2′,4′,6′-triisopropylbiphenyl-2-yl)phosphine (8.9 mg, 0.019 mmol), and Pd2(dba)3 (8.5 mg, 9.28 μmol). The tube was purged with argon, the solids were treated with dioxane (2.5 mL) and water (0.25 mL), the tube was sealed, and the contents were heated in an Initiator microwave reactor (Personal Chemistry, Biotage AB, Inc., Upssala, Sweden) at 130° C. for 30 min. The mixture was treated with H2O and extracted with EtOAc and 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-ethyl-5-fluoropyrimidin-2-yl)-1-tosyl-1H-indol-5-yl)-1,3,4-oxadiazol-2-amine (124 mg, 75%) as a light yellow foam. MS (ESI, pos. ion) m/z: 535.1 (M+1). 1H NMR (400 MHz, CDCl3) δ ppm 9.16 (1H, s), 8.46-8.53 (2H, m), 8.09 (1H, d, J=8.4 Hz), 7.94-8.00 (1H, m), 7.86 (2H, d, J=8.6 Hz), 7.25 (2H, d, J=8.6 Hz), 4.71 (1H, s), 2.89-2.99 (2H, m), 2.35 (3H, s), 1.50 (9H, s), 1.44 (3H, t, J=7.5 Hz).

Provenance & Evidence