反应详情

温度

-10 °C

(4-Bromo-phenyl)-hydroxy-acetic acid (97 g, 0.42 mol) is dissolved in 200 ml of acetone and cooled to −10° C. At this temperature 23 ml of concentrated sulfuric acid are added dropwise. After the addition is complete, the reaction mixture is stirred at −10° C. for further 30 minutes and is subsequently poured into a cooled (0° C.) solution of sodium carbonate (86 g, mol) in 800 ml of water. The crystalline 5-(4-bromo-phenyl)-2,2-dimethyl-[1,3]dioxolan-4-one is filtered, washed with ice-cold water and dried in the high-vacuum. 1H-NMR (300 MHz, CDCl3): 1.72 (s, 3H, CH3), 1.76 (s, 3H, CH3), 5.37 (s, 1H, CHO), 7.37 (d, 2H, CH arom.), 7.56 (d, 2H, CH arom.).

1. additionAfter the addition
2. additionis subsequently poured into
3. filtrationThe crystalline 5-(4-bromo-phenyl)-2,2-dimethyl-[1,3]dioxolan-4-one is filtered
4. washwashed with ice-cold water
5. customdried in the high-vacuum