Sodium hydride → (3S)-tetrahydro-furan-3-yl 4-isopropyl-1,4,6,7-tetrahydro-5H-imidazo[4,5-c]pyridine-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

NaH (0.40 g, 10.0 mmol, 60% dispersion in mineral oil) was suspended in anhydrous THF (20 mL), cooled to 0° C. and (S)-3-hydroxytetrahydrofuran (0.88 g, 0.68 mL, 10.0 mmol) was added. The suspension was stirred at 0° C. for 30 min then added to a solution of Intermediate 2 (3.30 g, 10.0 mmol, 70% pure) in THF (60 mL) and the reaction mixture was stirred at room temperature. Two additional such portions of NaH and (S)-3-hydroxytetrahydrofuran in THF were added after 5 and 29 h, respectively. After 2 d the reaction mixture was quenched with water (10 mL) and the solvents were removed in vacuo. The residue was dissolved in EtOAc (100 mL), washed with 1 M aq Na2CO3 solution (4×100 mL), dried (MgSO4) and the solvents were removed in vacuo. The residue was purified by column chromatography (normal phase, 20 g, Strata SI-1, silica gigatube, DCM (200 mL) followed by 2%, 4% and 5% MeOH in DCM (200 mL each)) and reverse phase HPLC (YMC ODS-A 100×20 mm, 5 μm, 25 mL/min, gradient 30% to 60% (over 7 min) then 100% (3 min) MeOH in 10% MeOH/water) to give (3S)-tetrahydro-furan-3-yl 4-isopropyl-1,4,6,7-tetrahydro-5H-imidazo[4,5-c]pyridine-5-carboxylate (34.8 mg, 1.1%) as a white solid.

Provenance & Evidence