1'-Benzyl-3H-spiro[2-benzofuran-1,4'-piperidine] → 3H-spiro[2-benzofuran-1,4'-piperidine]
Reaction equation
C([N:8]1[CH2:13][CH2:12][C:11]2([C:17]3[CH:18]=[CH:19][CH:20]=[CH:21][C:16]=3[CH2:15][O:14]2)[CH2:10][CH2:9]1)C1C=CC=CC=1>[Ni].CCO>[NH:8]1[CH2:13][CH2:12][C:11]2([C:17]3[CH:18]=[CH:19][CH:20]=[CH:21][C:16]=3[CH2:15][O:14]2)[CH2:10][CH2:9]1Participants
Reactant 1
Product 1
Reagents, catalysts & solvents 2
Procedure
1′-Benzyl-3H-spiro[2-benzofuran-1,4′-piperidine] (119 g, 425.9 mmol) was dissolved EtOH (1 L) under argon and treated with Raney nickel (12 g) at ambient temperature for 1 h to absorb impurities which tended to poison the catalyst. Raney nickel was filtered off and the filtrate was hydrogenated in a steel autoclave over 10% Pd/C (Degussa Nr. 1835) (12 g) at 5 bar hydrogen pressure and 40° C. for 19 h. According to HPLC there was still 2.7% of starting material present. Thus the catalyst was filtered off, fresh 10% Pd/C (4 g) was added to the filtrate, and hydrogenation under the same condition was continued for 24 h. Filtration of the catalyst and evaporation of EtOH gave a light yellow oil, which crystallized spontaneously upon stirring with heptane (1 L) to give a white solid (65 g, 80%). MS: m/z=190 [M+H]+.
Workup
- customto absorb impurities which
- filtrationRaney nickel was filtered off
- filtrationThus the catalyst was filtered off
- additionfresh 10% Pd/C (4 g) was added to the filtrate, and hydrogenation under the same condition
- waitwas continued for 24 h
- filtrationFiltration of the catalyst and evaporation of EtOH
- customgave a light yellow oil, which
- customcrystallized spontaneously
Sources & evidence
- ORD record
- ord-627a698f7a0c4733b85160b7c609626d
- Source dataset
- uspto-grants-2009_03
- Patent number
- US07498339B2
Reaction notes
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