Acetic Acid → Diethyl 2-((dimethylamino)methylene)-3-oxosuccinate

Beteiligte Stoffe

Reaktionsschritte

To a solution of diethyl oxalacetate sodium salt (100 g, 476 mmol) in ethanol (250.00 mL) was added 1,1-dimethoxy-N,N-dimethylmethanamine (113 g, 952 mmol) and the reaction was stirred at room temperature for 30 min. Acetic acid (54.5 mL, 952 mmol) was added slowly over a period of 3 h and stirred at room temperature for 24 h. The volatile components were evaporated under reduced pressure and the oily residue was purified by silica gel chromatography (750 g REDISEP® column, eluting with 30% EtOAc in hexane). Fractions containing the product were combined and evaporated to afford Intermediate 104A (43 g, 30.8%). MS(ES): m/z=244 [M+H]+; 1H NMR (400 MHz, CDCl3) δ ppm 7.84 (s, 1H), 4.31 (q, J=7.2 Hz, 2H), 4.18 (q, J=5.4 Hz, 2H), 3.35 (s, 3H), 3.04 (s, 3H), 1.36 (t, J=7.2 Hz, 3H), 1.26 (t, J=7.2 Hz, 3H).

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