Cesium carbonate → (+/-)-Ethyl 2-(5-cyanobenzo[d]oxazol-2-yl)-2-(5-methoxy-7-methyl-1H-indol-4-yl)propanoate

Participants

Reaction Conditions

Reaction Steps

To a solution of (±)-tert-butyl 4-(2-(5-cyanobenzo[d]oxazol-2-yl)-1-ethoxy-1-oxopropan-2-yl)-5-methoxy-7-methyl-1H-indole-1-carboxylate (Example 144-C) (44 mg, 0.087 mmol) in EtOH (874 μL), was added cesium carbonate (142 mg, 0.437 mmol). The reaction mixture was heated up to 60° C. and stirred for 2 hrs. The reaction mixture was quenched with a saturated solution of sodium bicarbonate at 0° C. The layers were separated and the aqueous layer was extracted with EtOAc (2×). The combined organic layers were dried over magnesium sulfate and concentrated to give crude product that was purified via FCC (4 g column): Heptane/AcOEt: 100/0 to 50/50 to obtain the title compound. 1H NMR (600 MHz, DMSO-d6) δ ppm 11.05 (br. s., 1H) 8.36-8.60 (m, 1H) 7.72-8.02 (m, 2H) 7.13 (t, J=2.93 Hz, 1H) 6.81 (s, 1H) 5.12 (dd, J=3.21, 1.83 Hz, 1H) 4.02-4.28 (m, 2H) 3.62 (s, 3H) 2.43-2.48 (m, 3H) 2.03 (s, 3H) 1.08 (t, J=7.11 Hz, 3H). HRMS calcd. for C23H21N3O4 (M+H)+ 404.1610. found 404.1619.

Provenance & Evidence