Hydroxyl synthesis (via ester): 

 

A solution of lithium alumiunhydride (34 ml, 34 mmol) in THF was added dropwise over 30 min to a stirred solution of ester comρound (14 g, 42 mmol) in THF (120 mL) at room temperature. After 2h, TLC showed no starting material left. The reaction mixture was stored in the fridge overnight and was quenched by the sequential addition of water (4 mL), aq NaOH (0.5 M, 4 mL) and water (4 mL). The mixture was filtered through CELITE (diatomaceous earth), washed thoroughly with EtOAc and the filtrate was concentrated to give hydroxyl compound. 

 

Patent reference: WO2010056717 (Merck)

Hydroxyl synthesis (via ketone):

 

1-(5-Fluoropyridin-2-yl)ethanone (11.3 g, (75% pure), 60.9 mmol) in MeOH was added sodium boronhydride (2.30 g, 60.9 mmol) potion wise at 0°C. After adding, the reaction mixture was warmed to room temperature and stirred at room temperature for 1 hour. Water (10 ml) was added and the solution was extracted with ether (2x50 ml). The combined organic layers were dried over sodium sulfate. After removal of solvent, the resulted residue was purified by column chromatography (ether) to give the title compound as a clear oil (7.5 g, 87%). 

 

Patent reference: WO2010020810 (Astrazeneca)

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