Dimethylformamide → 3-Cyano-4-(4-phenoxy-phenylamino)-pyrrolo[1,2-b]pyridazine-7-carboxylic acid ethyl ester

Participants

Reaction Steps

Compound 406E (110 mg, 0.476 mmol) was heated in POCl3 (1 ml) at 83-100° C. for 2 h. Excess POCl3 was removed on a rotary evaporator, and the residue was stripped with CH2Cl2 (2 ml). To the solid residue was added DMF (5 ml), K2CO3 (690 mg, 5 mmol) and 4-phenoxy-phenylamine (353 mg, 1.91 mmol) at 0° C. The reaction mixture was degassed and stirred at rt overnight. Solid was filtered off and the filtrate was concentrated, the residue was purified by silica gel flash column chromatography to give the 406 (147 mg, 78%) as a yellow solid (25% EtOAc—Hexanes). LCMS Found: (M+H)+=398.6

Provenance & Evidence