4-(N-Boc-amino)piperidine → tert-Butyl {1-[2-(5,7-difluoro-2-oxoquinolin-1(2H)-yl)ethyl]piperidin-4-yl}carbamate

Participants

Reaction Steps

(5,7-Difluoro-2-oxo-1(2H)-quinolinyl)acetaldehyde (2.1 g; 9.4 mmol) and 1,1-dimethylethyl 4-piperidinylcarbamate (2.82 g; 14.1 mmol) were dissolved in a 1:1 mixture of chloroform and MeOH (60 ml:60 ml) and stirred at rt for 1 h. This was then treated with NaBH(OAc)3 (8.92 g; 42.3 mmol) and stirred for a further 1 h. More 1,1-dimethylethyl 4-piperidinylcarbamate (470 mg; 2.35 mmol) was added and the reaction stirred under the same conditions for 20 mins, this was then treated with NaBH(OAc)3 (1.98 g; 9.4 mmol) and stirred for 25 mins. More 1,1-dimethylethyl 4-piperidinylcarbamate (470 mg; 2.35 mmol) was then added and the reaction stirred for 20 mins. More NaBH(OAc)3 (500 mg; 2.38 mmol) was then added to the reaction and it was stirred overnight at rt. The solvents were then removed and the crude residue purified by column chromatography on silica gel using a 0-15% MeOH/DCM gradient to give the desired product (2 g; 52%).

Provenance & Evidence