Diisopropylethylamine → N-Boc-2-Methyl-Piperidine

N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (0.46 g, 2.42 mmol) and 1-hydroxy-benzotriazole monohydrate(0.37 g, 2.41 mmol) were added to a solution of 2-methylpiperidine-1,4-dicarboxylic acid-1-tert-butylester (0.59 g, 2.42 mmol) in N,N-dimethylformamide (8 mL). After 30 min at 20° C. a solution of (2R)-2-amino-N-methyl-N-[(1R)-1-(3-methyl-1,2,4-oxadiazol-5-yl)-2-(2-naphthyl)ethyl]-3-(2-naphthyl)propionamide (as a trifluoroacetate) (1.0 g, 1.73 mmol) and diisopropylethylamine (0.22 g, 1.73 mmol) in N,N-dimethylformamide (4 mL) was added. After 18 h at 20° C. the reaction mixture was poured on water (100 mL) and extracted several times with ethyl acetate (total 60 mL). The collected organic phases were washed with aqueous citric acid (10%, 20 mL), a saturated solution of sodium hydrogen carbonate (20 mL) and water (3×20 mL). After drying (magnesium sulfate) the solution was concentrated in vacuo to give 1.25 g of crude 4-(1-{methyl-[1-(3-methyl-1,2,4-oxadiazol-5-yl)-2-(2-naphthyl)ethyl]carbamoyl}-2-(2-naphthyl)ethyl)-carbamoyl)-2-methylpiperidine-1-carboxylic acid tert-butyl ester that was used for the next step without further purification.

1. additionAfter 18 h at 20° C. the reaction mixture was poured on water (100 mL)
2. extractionextracted several times with ethyl acetate (total 60 mL)
3. washThe collected organic phases were washed with aqueous citric acid (10%, 20 mL)
4. dry with materialAfter drying (magnesium sulfate) the solution
5. concentrationwas concentrated in vacuo

ORD record

ord-83df415ff17f4abb8b83cb6ef7f61952

Source dataset

uspto-grants-2000_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06127391