The general procedure for the synthesis of 3-(4-morpholino)propionic acid from methyl 3-morpholino propionate was as follows: potassium hydroxide (485 mg, 8.6 mmol) was added to a solution of methyl 3-morpholino propionate (1 g, 5.7 mmol) in ethanol (20 mL) and the mixture was stirred for 2 hr at 80°C. The reaction was carried out using the same method as that used for the synthesis of methyl 3-morpholino propionate. Upon completion of the reaction, the solution was allowed to cool to room temperature and the pH was adjusted to 1 with 6 M hydrochloric acid. insoluble material was removed by filtration, and the volatiles in the filtrate were subsequently removed by evaporation. The resulting oil was ground with ether, the solid product was collected by filtration, washed with dichloromethane and dried under vacuum to give 3-morpholino propionic acid (993 mg, 89% yield) as a white solid. The structure of the product was confirmed by 1H NMR spectroscopy (DMSO-d6; CF3COOD): δ 2.83 (t, 2H), 3.13 (t, 2H), 3.36 (t, 2H), 3.46 (d, 2H), 3.73 (t, 2H), 3.97 (d, 2H). Mass spectrometry analysis (MS-ESI) showed a molecular ion peak of 159 [MH]+.
