Synthesis
1,1,3,3-tetramethoxypropane (23) (10 g) was used as a raw material, and a solution of water (H2O, 11 mL) with concentrated HCl (0.43 mL) was stirred at room temperature for 10 minutes. Subsequently, Br2 (3.1 mL) was slowly added dropwise to the above solution at room temperature for a controlled time of 50 minutes or more. After the dropwise addition was completed, the reaction mixture was continued to be stirred at room temperature for 20 minutes. After completion of the reaction, the mixture was concentrated under vacuum. The resulting residual solid was washed with water (H2O) to give the final target product 2-bromomalonaldehyde (24) (3.6 g, 39%) as a yellow solid. The melting point of the product was 147-148 °C; 1H NMR (CDCl3) δ 4.73-4.80 (1H,m),8.47 (2H,br s); FAB MS m/e (M-H)-149.
References
[1] Bioorganic and Medicinal Chemistry Letters, 2004, vol. 14, # 1, p. 235 - 238
[2] Patent: US2005/85492, 2005, A1. Location in patent: Page/Page column 25
[3] Bioorganic and Medicinal Chemistry, 2013, vol. 21, # 5, p. 1219 - 1233
[4] Organic and Biomolecular Chemistry, 2005, vol. 3, # 18, p. 3388 - 3398
[5] Patent: WO2004/67521, 2004, A1. Location in patent: Page 68
