Diisopropylethylamine → HCID 59331581, compound

Participants

Reaction Steps

To a solution (30 mL) of 2-[4-(cyclopropylsulfonyl)phenyl]-3-[(1R)-3-oxocyclopentyl]propanic acid in N,N-dimethylformamide were added N,N-diisopropylethylamine (1.89 mL), 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo(4,5-b)pyridinium 3-oxide hexafluorophosphate (1.52 g) and 5-cyclobutylisoxazol-4-amine hydrochloride (0.669 g), and the mixture was stirred at room temperature for 20 hr. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The extract was washed successively with water and saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:hexane=70:30-100:0, volume ratio). The obtained crude product was dissolved in ethanol (30 mL), palladium carbon (1.00 g) was added, and the mixture was purged with hydrogen (5 atm) and stirred at room temperature for 2 hr and at 50° C. for 2 hr. The reaction mixture was filtered to remove the catalyst, sodium hydroxide (0.160 g) was added to the filtrate, and the mixture was heated under reflux for 1.5 hr. To the reaction mixture was added ammonium chloride (0.243 g), and the mixture was cooled to room temperature and stirred at room temperature for 16 hr. The reaction mixture was concentrated, the obtained residue was suspended in acetone and the suspension was filtered to remove insoluble materials. The filtrate was concentrated, and the obtained residue was purified by silica gel column chromatography (ethyl acetate:hexane=60:40-100:0, volume ratio) to give the title compound (0.720 g, yield of 3 steps 45%) as a colorless oil. MS: 441 (MH+).

Provenance & Evidence