Nitrogen → HCID 13558282, compound

Participants

Reaction Steps

Triethylamine (3.88 g, 5.34 mL, 38.44 mM) was added at once under N2 to a stirred mixture of 2'-amino-4',5'-dimethoxyacetophenone (2.5 g, 12.8 mM) and ethyl 3-bromopropionate (17.43 mL, 96.2 mM) at room temperature. Immediately the reaction mixture solified. This was heated under N2 to 140°-150° C. (bath temp.) for a period of 4 hours during which the reaction mixture had partially liquified into a red-brown, viscous slurry. After cooling to room temperature it was treated with 5% NaHCO3 solution (50 mL) and then extracted with CH2Cl2 (3×60 mL). The combined organic extracts were washed with H2O, dried (Na2SO4) and evaporated in vacuo to remove CH2Cl2 (low vacuum) and excess 3-bromopropionate (under high vacuum at 50°-60° C.). The dark oily residue was chromatographed on a column of SilicAR CC-7 (300 g, 55.5×6 cm) packed in hexane. The sample was applied to the column in CH2Cl2 (50 mL) followed by elution with hexane and then with increasing proportions of ethyl acetate/hexane, collecting 1 L fractions. Fractions 10 and 11, afforded, upon evaporation to dryness 2'-(N-2-carbethoxyethylamino)-4',5'-dimethoxyacetophenone as a waxy crystalline solid (1.33 g, 35.2%), mp 73°-75° C.

Provenance & Evidence