The Darzens reaction between 2-fluorobenzaldehyde [57848-46-1] (1) and Ethyl 2-bromobutyrate [533-68-6] (2) gives ethyl 2-ethyl-3-(2-fluorophenyl)oxirane-2-carboxylate, CID:100942311 (3). A catalytic hydrogenation over Pd/C would give ethyl 2-[(2-fluorophenyl)methyl]-2-hydroxybutanoate, CID:77591056 (4). Saponification of the ester then gives 2-[(2-Fluorophenyl)methyl]-2-hydroxybutanoic acid, CID:53869347 (5). Treatment with 2 molar equivalents of sodium hydride apparently gives 2-Ethyl-2,3-dihydrobenzofuran-2-carboxylic acid [111080-50-3] (6). Treatment of the carboxylic acid with thionyl chloride then gives the acid chloride and subsequent treatment of this with ethylenediamine in the presence of trimethylaluminium completed the synthesis of Шаблон:Highlight (8).
↑Chapleo, Christopher B.; Myers, Peter L.; Butler, Richard C. M.; Davis, John A.; Doxey, John C.; Higgins, Stanley D.; Myers, Malcolm; Roach, Alan G.; Smith, Colin F. C. (1984). ".alpha.-Adrenoceptor reagents. 2. Effects of modification of the 1,4-benzodioxan ring system on .alpha.-adrenoreceptor activity". Journal of Medicinal Chemistry 27 (5): 570–576. doi:10.1021/jm00371a003.
↑Mayer, P.; Brunel, P.; Imbert, T. (1999). "A new efficient synthesis of efaroxan". Bioorganic & Medicinal Chemistry Letters 9 (20): 3021–3022. doi:10.1016/S0960-894X(99)00531-4.
↑Couture, K.; Gouverneur, V.; Mioskowski, C. (1999). "A new approach to the synthesis of efaroxan". Bioorganic & Medicinal Chemistry Letters 9 (20): 3023–3026.
doi:10.1016/S0960-894X(99)00530-2.
