Citric Acid → HCID 86669238, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 1,1-dimethylethyl[4-(4-{[1-methyl-3-({[(1-methylethyl)oxy]carbonyl}amino)-3-oxopropyl]amino}phenyl)-1H-imidazol-1-yl]acetate (for a preparation see intermediate 89) (980 mg, 2.21 mmol) in ethanol (20 mLl) was cooled to −15° C. The solution was treated with sodium borohydride (75 mg, 1.98 mmol) followed by magnesium chloride (1M in water, 2.43 mL, 2.43 mmol) maintaining the temperature below −10° C. The reaction mixture was stirred at a temperature lower than 0° C. for 1 h then at room temperature for 1 h. The suspension formed was poured onto a stirred mixture of citric acid (1.06 g, 5.51 mmol), HCl (1M in water, 25 mL) and DCM (15 mL). The resulting mixture was stirred at room temperature for 30 min and the layers were separated. The aqueous layer was basified by the addition of solid K2CO3 then was extracted with AcOEt (3×20 mL). The combined organic phases (DCM+EtOAc) were washed with water then brine, dried over MgSO4 and concentrated in vacuo. Purification of the residue by flash chromatography on silica gel (gradient: 0 to 2% MeOH in DCM) gave 1,1-dimethylethyl {(cis)-4-[2-methyl-4-({[(1-methylethyl)oxy]carbonyl}amino)-1,2,3,4-tetrahydro-6-quinolinyl]-1H-imidazol-1-yl}acetate (645 mg, 1.505 mmol, 68%) as an orange oil.

Provenance & Evidence