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TBS Deprotection

(TBAF)







Examples:


Example 1



TBAF (1M in THF, 30.6 mL, 30.6 mmol) was added dropwise to a solution of the SM (15.2 g, 25.5 mmol) in THF (150 mL) at RT. The reaction mixture was stirred for 2 days, after which time it was concentrated in vacuo. The resulting material was purified by Prep LC (330 g silica, 100% DCM to 95% DCM, 5% MeOH, 0.1% NH4OH) to provide the product. [11.9 g, 97%]


[Patent Reference: WO2015144799, page 94, (18.8 MB)]



Example 2



A mixture of the SM (319 mg, 0.848 mmol) and TBAF (221 mg, 0.848 mmol) in THF (20 mL) was stirred at RT overnight. Upon completion, the resulting solution was concentrated in vacuo to provide crude material which was purified by silica gel flash chromatography (1:1 PE/EtOAc) to provide the product. [220 mg, 99%]


[Patent Reference: WO2014152144, page 59, (4.6 MB)]



Example 3



The SM (130 mg, 0.33 mmol) was suspended in dry THF (5 mL) and cooled in an ice bath. TBAF (1M in THF, 0.65 mL, 0.65 mmol) was added and the reaction mixture was allowed to warm to RT and stir for 3 h. The mixture was concentrated in vacuo, diluted with EtOAc, and washed with sat aq NH4Cl. The org layer was concentrated to provide the crude product which was used directly in the next step. [143 mg]


[Patent Reference: WO2015078802, page 76, (3.8 MB)]