反应详情

To (S)-3-[4-(3-hydroxy-propyl)-phenoxy]-propane-1,2-diol (11.5 g, 50.9 mmol) in dry DMF (150 ml) is added pyridinium p-toluenesulfonate (1.28 g, 5 mmol) and 2,2-dimethoxypropane (31 ml, 250 mmol). The mixture is stirred at room temperature for 18 hours and then the solvent is removed in vacuo. The residue is dissolved in EtOAc (150 ml) and washed with water, saturated aqueous sodium hydrogen carbonate solution, brine, dried (MgSO4) and concentrated in vacuo. The residue is purified by chromatography on silica eluting with 1:4 EtOAc/iso-hexane to 1:1 EtOAc/iso-hexane to afford (3-[4-((R)-2,2-Dimethyl-[1,3]dioxolan-4-ylmethoxy)-phenyl]-propan-1-ol as a colourless oil; 1H NMR (CDCl3): 1.25 (1H, br), 1.39 (3H, s), 1.43 (3H, s), 1.85 (2H, pent, J=6.9 Hz), 2.63 (2H, tr, J=6.9 Hz), 3.63 (2H, tr, J=6.9 Hz), 3.90 (2H, m), 4.02 (1H, m), 4.12 (1H, m), 4.50 (1H, pent, J=6.8 Hz), 6.82 (2H, d, J=7.4 Hz), 7.10 (2H, d, J=7.4 Hz).

1. customthe solvent is removed in vacuo
2. dissolutionThe residue is dissolved in EtOAc (150 ml)
3. washwashed with water, saturated aqueous sodium hydrogen carbonate solution, brine
4. dry with materialdried (MgSO4)
5. concentrationconcentrated in vacuo
6. customThe residue is purified by chromatography on silica eluting with 1:4 EtOAc/iso-hexane to 1:1 EtOAc/iso-hexane