Pyridine → HCID 66783332, compound

Participants

Reaction Steps

O3′-tert.-butyldimethylsilyl-O5′-(2-(4-nitrophenoxycarbonyl)benzoyl)thymidine, PSNp-dT-Si (6f) (24.4 g, 39 mmol) was dissolved in dichloromethane (300 ml). Hydrogen fluoride in pyridine (65% HF, 12.6 ml, 450 mmol) was added and the mixture was stirred at ambient temperature for 5 hours. The reaction was quenched by the addition of solid calcium carbonate (25.9 g) and stirred for 1 hour. After removal of the solid material by filtration the organic phase was extracted with 5% sodium hydrogencarbonate solution (2 times 500 ml) and water (2 times 500 ml). The organic phase was dried over sodium sulfate and concentrated to a foam by evaporation. The foam was dissolved in dichloromethane (120 ml) and added dropwise to a mixture of hexanes and diethylether (8:2, v/v, 1500 ml). The precipitate was filtered off and washed with a small volume of hexanes. Further purification by column chromatography on silica gel (ethyl acetate/hexanes, gradient elution) afforded the product in 99.8% purity by RP-HPLC (18.4 g, 92%). ESI-MS (pos. mode) m/z 512 [M+H]+.

Provenance & Evidence