Cesium fluoride → tert-Butyl (1-{4-[2-(1,3-benzoxazol-2-yl)-9H-imidazo[1,2-d]pyrido[2,3-b][1,4]benzodiazepin-3-yl]phenyl}cyclobutyl)carbamate

Participants

Reaction Conditions

Reaction Steps

A mixture of tert-butyl {1-[4-(2-bromo-9H-imidazo[1,2-d]pyrido[2,3-b][1,4]benzodiazepin-3-yl)phenyl]cyclobutyl}carbamate (50.0 mg, 0.0895 mmol), 2-(tributylstannyl)-1,3-benzoxazole (81.2 mg, 0.179 mmol), bis (tri-tert-butylphosphine)palladium(0) (9.15 mg, 0.0179 mmol) and cesium fluoride (88.4 mg, 0.582 mmol) in 1,4-dioxane (1.00 mL) was heated at 130° C. under microwave irradiation for 2 hours under nitrogen. After cooling to room temperature, the mixture was diluted with water and extracted with EtOAc (×3). The combined organic layer was dried over anhydrous Na2SO4 and concentrated. The residue was purified by PTLC (EtOAc/hexane=1:1, DCM/EtOAc=1:1) to afford desired product (11.3 mg, 21.2%) as white solid. 1HNMR (CDCl3) 500 MHz δ: 8.27 (dd, J=7.7, 1.7 Hz, 1H), 8.08-8.02 (m, 1H), 7.75-7.68 (m, 1H), 7.52-7.38 (m, 5H), 7.37-7.25 (m, 3H), 7.20-7.14 (m, 1H), 6.98 (d, J=8.0 Hz, 1H), 6.92-6.81 (m, 1H), 6.63 (dd, J=8.0, 4.6 Hz, 1H), 6.45 (s, 1H), 5.20 (s, 1H), 2.68-2.25 (m, 4H), 2.22-2.09 (m, 1H), 1.97-1.86 (m, 1H), 1.54-1.11 (m, 9H).

Provenance & Evidence