1,4-Dioxane → N-(3-(2-((2-methoxy-4-(piperazin-1-yl)phenyl)amino)-5-methyl-7-oxopyrido[2,3-d]pyrimidin-8(7H)-yl)phenyl)acrylamide

Participants

Reaction Conditions

Reaction Steps

To a suspension of tert-butyl 4-(4-amino-3-methoxyphenyl)piperazine-1-carboxylate (18a, 539 mg, 1.753 mmol) and N-(3-(5-methyl-2-(methylsulfinyl)-7-oxopyrido[2,3-d]pyrimidin-8(7H)-yl)phenyl)acrylamide (5b, 432 mg, 1.173 mmol) in tert-butanol (15 mL) at RT was added DIEA (0.61 mL, 3.52 mmol) followed by dioxane (6 mL). The reaction mixture was heated in a heating block at 90° C. for 20 h. LC-MS analysis indicated roughly 13% conversion to the desired product along with unreacted starting materials. The reaction mixture was concentrated on the rotovap and the crude residue was suspended in Et2O and filtered. The greenish brown amorphous solid was washed with Et2O (3×20 mL) and this removed most of the aniline starting material (18a). The crude material contained roughly 19% of the desired product (18b) along with recovered 5b. m/z (ESI, +ve ion) 611.9 (M+H)+. The crude residue was used in the subsequent step without further purification.

Provenance & Evidence