ethyl 4-bromo-1-(5-chloro-2-nitrobenzyl)-1H-pyrrole-2-carboxylate → ethyl 1-(2-amino-5-chlorobenzyl)-4-bromo-1H-pyrrole-2-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a well-stirred solution of ethyl 4-bromo-1-(5-chloro-2-nitrobenzyl)-1H-pyrrole-2-carboxylate (9.1 g, 23.48 mmoles) in acetic acid (60.00 mL) at 70° C., add iron (5 equiv; 6.56 g, 117.38 mmoles) in portions over 0.5 h. Halfway through the addition, observe an exotherm to maintain a temperature of 85° C. with the oil-bath removed. The reaction mixture will get thicker as the exotherm dissipates and the rest of the iron can be added. Stir at 85° C. for 0.5 h. Cool to room temperature and pour onto water (200 mL). Extract into chloroform (2×200 mL). Combine organic layers and wash with water (2×100 mL) then saturated aqueous NaHCO3 solution. Dry over Na2SO4, filter and evaporate to the title compound as an orange oil (7.7 g, 92% yield). MS (m/z): 358.98 (M+1).

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