Cesium carbonate → 1-(5-Tert-butylisoxazol-3-yl)-3-[3-(6,7-diethoxyquinazolin-4-yloxy)phenyl]urea

Participants

Reaction Conditions

Reaction Steps

A mixture of 1-(5-tert-butylisoxazol-3-yl)-3-(3-hydroxyphenyl)urea from Example 1A (0.137 g, 0.5 mmol), 4-chloro-6,7-diethoxyquinazoline from the previous step (0.126 g, 0.5 mmol), and Cs2CO3 (0.326 g, 1 mmol) in isopropanol (6 mL) was heated at 90° C. for 4 hours. The reaction was quenched with water and extracted with CH2Cl2. Extracts were dried over MgSO4 and concentrated under reduced pressure. The residue was purified by silica gel chromatography with EtOAc/hexane as eluant to afford 1-(5-tert-butylisoxazol-3-yl)-3-[3-(6,7-diethoxyquinazolin-4-yloxy)phenyl]urea as a solid. 1H NMR (300 MHz, DMSO-d6) δ 9.59 (s, 1H), 9.03 (s, 1H), 8.56 (s, 1H), 7.57 (m, 1H), 7.55 (s, 1H), 7.40 (t, 1H), 7.37 (s, 1H), 7.25 (d, 1H), 6.96 (dd, 1H), 6.47 (s, 1H), 4.26 (m 4H), 1.43 (m, 6H), 1.27 (s, 9H).

Provenance & Evidence