Sodium hydride → HCID 58408394, compound

Participants

Reaction Conditions

Reaction Steps

NaH (0.19 g, 5.00 mmol, 60% dispersion in mineral oil) was suspended in THF (10 mL) at 0° C. and (R)-1-methylpyrrolidin-3-ol (0.47 mL, 4.00 mmol) was added. The suspension was stirred at 0° C. for 30 min and added to a solution of Intermediate 2 (1.33 g, 4.00 mmol) in THF (10 mL) and the reaction mixture was stirred at room temperature. Two additional such portions of NaH and (R)-1-methylpyrrolidin-3-ol in THF were added after 18 and 26 h, respectively. After 44 h 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%, 5%, 10% and 20% MeOH in DCM (200 mL)) and reverse phase HPLC (Phenomenex Synergi, RP-Hydro 150×10 mm, 10 μm, 15 mL per min, gradient 0% to 30% (over 12 min) to 100% (over 3 min) MeOH in water [1% formic acid]). The residue was de-salted using K2CO3 in DCM to give (3R)-1-methylpyrrolidin-3-yl 4-isopropyl-1,4,6,7-tetrahydro-5H-imidazo-[4,5-c]pyridine-5-carboxylate (32.3 mg, 2.7%) as a colourless gum.

Provenance & Evidence