tert-Butyldimethylsilyl trifluoromethanesulphonate → HCID 90272385, compound

Participants

Reaction Conditions

Reaction Steps

Into a 500 ml flask, the product from step (a) (6.01 g, 20.65 mmol) dissolved in DCM (100 ml) was added. The solution was cooled to 0° C. and TEA (17.27 ml, 123.91 mmol) was added, followed by TBDMS-triflate (14.222 ml, 61.95 mmol). After 10 minutes, the ice bath was removed and the mixture was stirred at room temperature for 16 hours. The contents were washed with saturated aqueous NaHCO3, 1M citric acid, saturated aqueous NaHCO3, brine, and dried over Na2SO4. Evaporation of solvent yielded a brown liquid which was immediately dissolved in acetonitrile (100 ml). The solution was cooled to 0° C. and Selectfluor (14.6 g, 41.3 mmol) was added portion-wise at 0° C. over 30 minutes. The flask was then warmed to room temperature and stirred for 1 hour. The contents were partitioned between DCM and water and the aqueous layer was extracted with DCM (3×). The combined DCM extracts were washed with brine, dried over Na2SO4, and solvent evaporated in vacuo to give the crude product. Purification by silica-gel chromatography (gradient elution: 0 to 40% EtOAc) gave the sub-title product an off-white solid (5.1 g). 1H NMR (300 MHz, CDCl3) δ7.45 (d, J=7.8 Hz, 1H); 7.23 (d, J=7.5 Hz, 1H); 4.16 (t, J=6.9 Hz, 2H); 3.63-3.57 (m, 6H); 3.46 (t, J=12.9 Hz, 2H); 3.01-2.98 (m, 2H); 1.27 (t, J=7.2 Hz, 3H); MS: ESI (positive): 310 (M+1).

Provenance & Evidence