Synthesis
General procedure for the synthesis of 4-morpholinomethylbenzoic acid from methyl 4-(morpholinomethyl)benzoate: to a stirred solution of methyl 4-(morpholinomethyl)benzoate (4.0 g, 17.0020 mmol, 1.0 eq.) in methanol (40 mL) was added slowly at 0 °C an aqueous 1N NaOH solution (136.0 mL, 136.0 mmol, 8.0 equivalent). The reaction mixture was stirred at room temperature overnight. The progress of the reaction was monitored by TLC and after confirming the completion of the reaction, the reaction mixture was cooled to 0 °C and neutralized with 1N HCl to pH neutral. Subsequently, the solvent was removed by evaporation under reduced pressure. Methanol (40 mL) and dichloromethane (60 mL) were added to the resulting solid and stirred at room temperature for 25 minutes. The mixture was filtered and the filtrate was evaporated under reduced pressure to recover the product. The above extraction and evaporation process was repeated twice to finally obtain a white solid product (3.0 g, yield: 79.57%), which could be used in the next reaction without further purification. The structure of the product was confirmed by 1H NMR (300 MHz, CDCl3) and ESI-MS: 1H NMR δ 8.04 (d, J = 8.1 Hz, 2H), 7.50 (d, J = 8.1 Hz, 2H), 3.81 (m, 4H), 3.71 (s, 2H), 2.62 (m, 4H); ESI-MS: m/z 222.01 (M + H)+.
References
[1] Patent: WO2018/29604, 2018, A1. Location in patent: Page/Page column 45
[2] Bioorganic and Medicinal Chemistry, 2016, vol. 24, # 2, p. 179 - 190
