Dimethylformamide dimethyl acetal → HCID 58980884, Verbindung

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of methyl 3-amino-5-(4-chlorophenyl)-2-thiophenecarboxylate (2.0 g, 7.47 mmol, Maybridge, Inc) in ethanol (20 mL) was added dimethylformamide dimethyl acetal (2.5 mL, 2.5 eq, Aldrich). The reaction mixture was refluxed in a 90° C. oil bath for 3 h at which point the solvents were removed by rotary evaporation. Coevaporation with toluene removed the excess dimethylformamide dimethyl acetal. To the resulting residue was added ethanol (20 mL) and 4-(2,2-diethoxyethoxy)-3-methoxyaniline (2.3 g, 1.2 eq, Example H1). The reaction mixture was heated to 100° C. for 36 hours. The solvent was removed by rotary evaporation and the product purified by column chromatography followed by recrystallization from hot MeOH yielding the intermediate (0.82 g, 22%). 1H NMR (CDCl3) δ 1.22 (6H, t), 3.63-3.83 (4H, m), 3.90 (3H, s), 4.14 (2H, d, J=5.3 Hz), 4.92 (1H, t, J=5.2 Hz), 6.97 (2H), 7.06 (1H, d, J=8.5 Hz), 7.46 (2H, d, J=8.5 Hz), 7.58 (1H, s), 7.68 (2H, d, J=8.4 Hz), 8.24 (1H, br, s). LCMS m/z=501 (m+H+).

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