[OH:1][C:2]1[CH2:3][C:4](=[O:7])[O:5][CH:6]=1.[C:8](O)([CH3:11])([CH3:10])[CH3:9].S(=O)(=O)(O)O>O>[C:8]([CH:3]1[C:2]([OH:1])=[CH:6][O:5][C:4]1=[O:7])([CH3:11])([CH3:10])[CH3:9]To 4-hydroxy-2-furanone (50 g, 0.5 mol) in tert-butanol (50 ml, 0.53 mol) was added concentrated sulfuric acid (25 ml). The mixture was heated at 40° C. for 20 h then allowed to cool. Water (250 ml) was added and the mixture was extracted with diethyl ether (3×250 ml), the diethyl ether layers were combined, washed with brine (250 ml), dried (Na2SO4), filtered and concentrated in vacuo to give a brown solid. The solid was purified by silica gel chromatography with 0%→100% ethyl acetate/isohexane as eluent followed by two recrystallisations from ethyl acetate/isohexane (1:1) to afford the required product (5.75 g). Data for the title compound: 1H NMR (400 MHz, DMSO) δ 1.21 (9H, s), 4.48 (2H, s), 11.40 (1H, s); MS (ES+) m/e 156 [MH]+.
Wird geladen…
