ethyl 4-amino-1-benzylpiperidine-3-carboxylate

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Amino-1-benzyl-1,2,5,6-tetrahydro-pyridine-3-carboxylic acid methyl ester BH3 salt was heated in ethanol with NaOH 25%. After 72 h at 50° C. the mixture was cooled, washed with water/ice and extracted with AcOEt. The extract was washed with brine and dried over sodium sulfate. Removal of the solvent under reduced pressure gave an yellow oil. To a suspension of 4-amino-1-benzyl-1,2,5,6-tetrahydro-pyridine-3-carboxylic acid methyl ester (21 g) in 200 ml THF was added 50 ml TFA at 10° C. under an argon atmosphere. After stirring for 15 min at 0° C., NaBH4 (6.43 g) was added over a period of 75 min at 10° C. The mixture was stirred for additional 90 min at 0° C. After adding 100 ml NH4Cl saturated, the solution was extracted two times with CH2Cl2. The combined extracts were washed with water/ice and brine and dried over sodium sulfate. Evaporation of the solvent gave a yellow oil of the title compound which was taken for the next step without purification washed with water/ice extracted with AcOEt The extract was washed with brine dried over sodium sulfate Removal of the solvent under reduced pressure gave an yellow oil The mixture was stirred for additional 90 min at 0° C the solution was extracted two times with CH2Cl2 The combined extracts were washed with water/ice and brine dried over sodium sulfate Evaporation of the solvent

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Amino-1-benzyl-1,2,5,6-tetrahydro-pyridine-3-carboxylic acid methyl ester BH3 salt was heated in ethanol with NaOH 25%. After 72 h at 50° C. the mixture was cooled, washed with water/ice and extracted with AcOEt. The extract was washed with brine and dried over sodium sulfate. Removal of the solvent under reduced pressure gave an yellow oil. To a suspension of 4-amino-1-benzyl-1,2,5,6-tetrahydro-pyridine-3-carboxylic acid methyl ester (21 g) in 200 ml THF was added 50 ml TFA at 10° C. under an argon atmosphere. After stirring for 15 min at 0° C., NaBH4 (6.43 g) was added over a period of 75 min at 10° C. The mixture was stirred for additional 90 min at 0° C. After adding 100 ml NH4Cl saturated, the solution was extracted two times with CH2Cl2. The combined extracts were washed with water/ice and brine and dried over sodium sulfate. Evaporation of the solvent gave a yellow oil of the title compound which was taken for the next step without purification washed with water/ice extracted with AcOEt The extract was washed with brine dried over sodium sulfate Removal of the solvent under reduced pressure gave an yellow oil The mixture was stirred for additional 90 min at 0° C the solution was extracted two times with CH2Cl2 The combined extracts were washed with water/ice and brine dried over sodium sulfate Evaporation of the solvent