4-AMINO-1-BENZYL-PIPERIDINE-4-CARBOXYLIC ACID

In a 20 L reactor 2.4 kg sodium hydroxide were dissolved in 10 L water. The solution was mixed with 614 g 1.38 (8-benzyl-1 , 3, 8-triaza-spiro[4.5]decane-2, 4-dione) and the resulting reaction suspension was heated to 80°C. When 80°C was reached, the reaction mixture was heated in steps of 10°C. When the temperature reached 105°C the mixture started to foam strongly. Stirring was continued at 108°C overnight. The reaction mixture was cooled to 10°C and 5 L concentrated hydrochloric acid were added dropwise to obtain a pH 7-8. During the addition the temperature was kept at 23°C. The precipitate was filtered and dried in vacuo at 40°C over 3 days, then at 80°C overnight.Yield: 469.7 g I.39 (85percent of theory)In a 20 L reactor 2.4 kg sodium hydroxide were dissolved in 10 L water. The solution was mixed with 614 g I.38 (8-benzyl-1, 3, 8-triaza-spiro[4.5]decane-2, 4-dione) and the resulting reaction suspension was heated to 80° C. When 80° C. was reached, the reaction mixture was heated in steps of 10° C. When the temperature reached 105° C. the mixture started to foam strongly. Stirring was continued at 108° C. overnight. The reaction mixture was cooled to 10° C. and 5 L concentrated hydrochloric acid were added dropwise to obtain a pH 7-8. During the addition the temperature was kept at 23° C. The precipitate was filtered and dried in vacuo at 40° C. over 3 days, then at 80° C. overnight. [0270] Yield: 469.7 g I.39 (85percent of theory)Step 2: 4-amino-1-benzylpiperidine-4-carboxylic acid: Lithium hydroxide monohydrate (12.8 g, 306 mmol) was added to a suspension of the crude product obtained in step 1 (15.8 g, 61.2 mmol) in water (198 mL) and the mixture was refluxed overnight. The remaining solids were filtered off, washed with water and discarded. The filtrate was acidified to 5-6 with cHCI and concentrated to dryness. The residue was suspended in MeOH (50 mL) and the solids were collected by filtration, washed with MeOH (2x 10 mL) and dried under vacuum to yield the title compound (12.1 g, 85percent yield). HPLC retention time (method A): 0.95 min; MS: 235.1 (M+H).

Molecular Weight:234.29
XLogP3:-1.5
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:4
Rotatable Bond Count:3
Exact Mass:234.136827821
Monoisotopic Mass:234.136827821
Topological Polar Surface Area:66.6
Heavy Atom Count:17
Complexity:267
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes