3-(4-Nitrophenyl)-beta-alanine

General procedure: A mixture of appropriate aldehyde 2.40 g (1-15), 2.44 g ofmalonic acid and 3.54 g of ammonium acetate (1:1.1:2.3), in 200mLof the 1-butanol was refluxed for 1.5-2 h until the evolution of CO2ceased. The precipitate formed was filtered and washed withboiling 1-butanol (2 x 50 mL), boiling ethanol (2 x 50 mL) and100mL of water. Precipitates were dried at 80-100 °C for 8-10 h.Purity of product was checked by TLC, and yield obtained about65-80percent in each reaction.To a hot solution of sodium ethoxide prepared from sodium (9.33 g, 405 mmol) and EtOH (330 ml) was added a hot solution of hydroxylamine hydrochloride (28.17 g, 405 mmol) in water (18 ml). A white precipitate was formed immediately. The mixture was cooled rapidly and the solid removed by filtration and washed with EtOH (40 ml). The filtrate was then returned to the reaction flask and 4-nitrocinnamic acid (30 g, 155 mmol) was added. The mixture was heated to reflux overnight. The resulting mixture was cooled to 0° and the precipitate filtered off and the solid washed with EtOH (50 ml), water (50 ml) and finally EtOH (50 ml) to give the title compound as a pale yellow solid (16 g, 49percent). δH (DEXAMPLE 38