反应详情

8.7 g (25 mmol) of diethyl 2-formylamino-4-bromomethyl-hept-3-ene-1,7-dicarboxylate and 21 ml (75 mmol) of triisopropylphosphite (90%) are heated to 80°-90° C. and the mixture is stirred for 19 hours under a pressure of ca. 100 mbar. Excess triisopropylphosphite is removed by distillation and the residue obtained after evaporation is chromatographed over 150 g of silica gel first with ethyl acetate and then with ethyl acetate/ethanol (9:1) as eluant, giving diethyl E-2-formylamino-4-diisopropylphosphonomethyl-hept-3-ene-1,7-dicarboxylate as a yellowish oil.

1. customExcess triisopropylphosphite is removed by distillation
2. customthe residue obtained
3. customafter evaporation
4. customis chromatographed over 150 g of silica gel first with ethyl acetate