Diisopropylethylamine → tert-butyl 4-{3-[(3R)-3-{[1-(5-bromopyridin-3-yl)-3-methoxy-3-oxopropyl]carbamoyl}piperidin-1-yl]-3-oxopropyl}piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

3.324 g (9.02 mmol) (3R)-1-{3-[1-(tert-butoxycarbonyl)piperidin-4-yl]propanoyl}piperidine-3-carboxylic acid (Bioorg. Med. Chem. 13 (2005) 4343-4352, Compound 10) were suspended in 52 ml N,N-dimethylformamide and cooled to 0° C. 3.694 g (9.71 mmol) HATU, a solution of 1.798 g (6.94 mmol) 3-amino-3-(5-bromo-pyridin-3-yl)-propionic acid methyl ester in 78 ml N,N-dimethylformamide and 3.56 ml (20.82 mmol) N-ethyl-diisopropylamine were added. The mixture was stirred at 0° C. for 5 minutes and at room temperature for 24 hours. 160 ml water were added and the mixture extracted with 280 ml dichloromethane. The organic phase was washed with water, dried over sodium sulfate and concentrated in vacuum. Chromatography over 55 g basic silica gel (dichloromethane/ethanol 100/0-97/3-94/6) gave 4395 mg (104%) tert-butyl 4-{3-[(3R)-3-{[1-(5-bromopyridin-3-yl)-3-methoxy-3-oxopropyl]carbamoyl}piperidin-1-yl]-3-oxopropyl}piperidine-1-carboxylate.

Provenance & Evidence