Dimethylformamide → HCID 13922984, compound

Participants

Reaction Steps

To a 0° C. solution of dimethylformamide (7.5 mL, 0.097 mol) in dichloroethane (20 mL) is added dropwise phosphorous oxychloride (9.0 mL, 0.097 mol). After stirring for 3.5 hours at room temperature, a solution of ethyl 3-(2,5-dimethoxyanilino)crotonate (25.8 g, 0.097 mol) in dichloroethane (130 mL) is added dropwise at 25° C. The resulting solution is heated at reflux temperature for 3 hours. After cooling to room temperature, the reaction is quenched by the addition of an aqueous ammonium chloride solution. Methylene chloride (200 mL) is added and the layers are separated. The organic layer is dried over anhydrous magnesium sulfate and concentrated in vacuo to give a residue. The residue is purified by chromatography using silica gel and ethyl acetate in hexanes as eluant to yield the title compound (34 g, 100%) as a yellow solid identified by IR and NMR spectral analyses.

Provenance & Evidence