Ammonium formate → Ethyl 5-{(tert-butoxycarbonyl)[2-(2-hydroxyphenyl)ethyl]amino}-5,6,7,8-tetrahydroquinoline-2-carboxylate

Temperature

80 °C

10 g (15.11 mmol) of (−)-ethyl 5-{(tert-butoxycarbonyl)[2-(2-{[4-(5-methyl-1,3-benzoxazol-2-yl)-benzyl]oxy}-phenyl)ethyl]amino}-5,6,7,8-tetrahydroquinoline-2-carboxylate (Enantiomer 2, Example 26A) were dissolved in 500 ml of ethanol, and 9.53 g (151.10 mmol) of ammonium formate and 161 mg (1.51 mmol) of 10% palladium on activated carbon were added. The reaction mixture was then heated to 80° C. and stirred at this temperature overnight. The mixture was then cooled to room temperature, another 100 mg of the palladium catalyst were added and the mixture was stirred at 80° C. for a further 6 h. The reaction mixture was then once more cooled to room temperature and filtered, and the filtrate was evaporated to dryness. The residue obtained was purified chromatographically on silica gel (mobile phase: cyclohexane/ethyl acetate 20:1→2:1). This gave 6.55 g (14.87 mmol, 98% of theory) of the title compound.

1. temperatureThe mixture was then cooled to room temperature
2. stirringthe mixture was stirred at 80° C. for a further 6 h
3. temperatureThe reaction mixture was then once more cooled to room temperature
4. filtrationfiltered
5. customthe filtrate was evaporated to dryness
6. customThe residue obtained
7. customwas purified chromatographically on silica gel (mobile phase: cyclohexane/ethyl acetate 20:1→2:1)

ORD record

ord-e22fc27172544c6e95e72ebb93c7712d

Source dataset

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08981104B2