Propanal → 2-(6Tert-butoxycarbonylamino-pyridin-3-ylmethyl)-pent-2-enoic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of NaH (290.5 mg, 60% in mineral oil, 7.5 mmol) in THF (25 mL) at 0° C. was added a solution of 3-(6-tert-butoxycarbonylamino-pyridin-3-yl)-2-(diethoxy-phosphoryl)-propionic acid ethyl ester (2.5 g, 5.81 mmol) in THF (30 mL). The reaction mixture was allowed to stir at 0° C. for 1 h. To the reaction was added propionaldehyde (725 mg, 12.5 mmol) dropwise at 0° C. The reaction mixture was allowed to stir at room temperature for 16 h. Propionaldehyde (2.5 g) was added and the mixture was stirred at room temperature for an additional 16 h. The reaction was quenched with the slow addition of saturated aqueous NH4Cl (30 mL). The mixture was extracted with EtOAc, washed with brine and dried. The crude product was purified by column chromatography (EtOAc/hexane, 1:8) to give 2-(6tert-butoxycarbonylamino-pyridin-3-ylmethyl)-pent-2-enoic acid ethyl ester as a mixture of isomers (1.2 g, 60%).

Provenance & Evidence