反应详情

To a solution of 225 (300 mg, 0.83 mmol) in DCM (5 ml) was added TEA (0.23 ml, 1.65 mmol) and 3,4,5-trimethoxybenzoyl chloride (228 ml, 0.99 mmol). The reaction mixture was stirred at rt for 12 h. Water (10 ml) was added and the aqueous layer was extracted with DCM (3×30 ml). The combined organic phases were washed with sat. aq. NaHCO3 (10 ml) and brine (10 ml), dried (MgSO4) and concentrated in vacuo. Purification (flashmaster: 20 g, gradient elution 100% hex to 100% EtOAc over 25 min) afforded the title compound (240 mg, 52%) as a colourless oil. 1H NMR (270 MHz; CDCl3) 1.04 (18H, d, J=6.7 Hz, 6×CH3CH), 1.14-1.24 (3H, m, 3×CH), 1.55 (6H, s, 2×CH3), 2.74 (2H, s, CH2), 3.80 (3H, s, OCH3), 3.85 (6H, s, 2×OCH3), 3.86 (3H, s, OCH3), 4.19 (2H, s, CH2), 6.53 (1H, s, CH), 6.56 (2H, s, 2×CH), 6.71 (1H, s, CH). LC/MS (ES+) tr=0.2.23 min, m/z 580.24 (M++Na). HRMS (ES+) calcd for C31H47NO6Si (M++H) 558.3245, found 558.3237.

1. extractionthe aqueous layer was extracted with DCM (3×30 ml)
2. washThe combined organic phases were washed with sat. aq. NaHCO3 (10 ml) and brine (10 ml)
3. dry with materialdried (MgSO4)
4. concentrationconcentrated in vacuo
5. customPurification (flashmaster: 20 g, gradient elution 100% hex to 100% EtOAc over 25 min)