Ammonium Hydroxide → Methyl 4-amino-1-benzyl-1,2,5,6-tetrahydropyridine-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

rac-1-Benzyl-4-oxo-piperidine-3-carboxylic acid methyl ester (25 g) was suspended in 100 ml ammonium hydroxide 25% and heated at 50° C. during 18 h. The mixture was cooled with ice and then, NaBH4 (1 g) was added in several portions. Stirring was continued for 18 h at ambient temperature and the mixture was diluted with water/ice, with cooling, and extracted with AcOEt. The organic extract was washed with brine and dried over sodium sulfate. Removal of the solvent under reduced pressure gave a brown oil which was purified by column chromatography (silica gel, heptane/AcOEt, 1/1) and precipitated (AcOEt/heptane) to give 12.1 g (56%) of the title compound as white solid and 6 g (25%) of the title compound as its borane salt.

Provenance & Evidence