乙基 2-[2-(2-乙氧基-2-氧乙基)-1,3-二氧戊环-2-基]乙酸甲酯

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A solution of diethyl 1,3-acetonedicarboxylate (12 g, 59.3 mmol), ethyleneglycol (9.93 mL, 178 mmol), and p-toluenesulfonic acid monohydrate (564 mg, 2.97 mmol) in benzene (80 mL) was refluxed under heating removing water for 10 h by Dean-Stark trap. The benzene layer was washed with a saturated aqueous sodium bicarbonate solution and brine. The solvent was distilled away and the residue obtained was purified by flash chromatography (10 to 40% EtOAc in heptanes) yielding diethyl 2,2′-(1,3-dioxolane-2,2-diyl)diacetate (42%). LCMS (m/z): 247.2 (MH+), 0.65 min; 1H NMR (400 MHz, CDCl3) δ ppm 4.17 (q, J=7.04 Hz, 4H) 4.03 (s, 4H) 2.95 (s, 4H) 1.27 (t, J=7.24 Hz, 6H). under heating removing water for 10 h by Dean-Stark trap The benzene layer was washed with a saturated aqueous sodium bicarbonate solution and brine The solvent was distilled away the residue obtained was purified by flash chromatography (10 to 40% EtOAc in heptanes)

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A solution of diethyl 1,3-acetonedicarboxylate (12 g, 59.3 mmol), ethyleneglycol (9.93 mL, 178 mmol), and p-toluenesulfonic acid monohydrate (564 mg, 2.97 mmol) in benzene (80 mL) was refluxed under heating removing water for 10 h by Dean-Stark trap. The benzene layer was washed with a saturated aqueous sodium bicarbonate solution and brine. The solvent was distilled away and the residue obtained was purified by flash chromatography (10 to 40% EtOAc in heptanes) yielding diethyl 2,2′-(1,3-dioxolane-2,2-diyl)diacetate (42%). LCMS (m/z): 247.2 (MH+), 0.65 min; 1H NMR (400 MHz, CDCl3) δ ppm 4.17 (q, J=7.04 Hz, 4H) 4.03 (s, 4H) 2.95 (s, 4H) 1.27 (t, J=7.24 Hz, 6H). under heating removing water for 10 h by Dean-Stark trap The benzene layer was washed with a saturated aqueous sodium bicarbonate solution and brine The solvent was distilled away the residue obtained was purified by flash chromatography (10 to 40% EtOAc in heptanes)