tert-butyl 1-benzyl-1,6-diazaspiro[3.3]heptane-6-carboxylate

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

Procedure: tert-Butyl 1-benzyl-1,6-diazaspiro[3.3]heptane-6-carboxylate (1.79 g, 6.21 mmol) was dissolved in methanol (33 mL), and Pd (10% on charcoal; 628 mg, 590 μmol) was added. A hydrogen atmosphere (balloon) was built up, and the mixture was stirred at ambient temperature for 24 h. Further Pd (10% on charcoal; 100 mg, 94 μmol, 0.015 equiv) was added and stirring under an hydrogen atmosphere was continued for another 24 h. The crude suspension was filtered over celite and the filter cake thoroughly washed with methanol, and the filtrate was concentrated under reduced pressure. To a solution of the residue in diethylether (140 mL) was added a solution of anhydrous oxalic acid (279 mg, 3.1 mmol) in ethanol (0.6 mL), upon which a precipitate formed immediately. The solid was filtered and dried under reduced pressure to give the title compound (1.18 g, 78%) as an amorphous colorless solid. MS (EI) m/e: 199.2 (M+H)+. stirring under an hydrogen atmosphere was continued for another 24 h The crude suspension was filtered over celite the filter cake thoroughly washed with methanol the filtrate was concentrated under reduced pressure upon which a precipitate formed immediately The solid was filtered dried under reduced pressure

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

Procedure: tert-Butyl 1-benzyl-1,6-diazaspiro[3.3]heptane-6-carboxylate (1.79 g, 6.21 mmol) was dissolved in methanol (33 mL), and Pd (10% on charcoal; 628 mg, 590 μmol) was added. A hydrogen atmosphere (balloon) was built up, and the mixture was stirred at ambient temperature for 24 h. Further Pd (10% on charcoal; 100 mg, 94 μmol, 0.015 equiv) was added and stirring under an hydrogen atmosphere was continued for another 24 h. The crude suspension was filtered over celite and the filter cake thoroughly washed with methanol, and the filtrate was concentrated under reduced pressure. To a solution of the residue in diethylether (140 mL) was added a solution of anhydrous oxalic acid (279 mg, 3.1 mmol) in ethanol (0.6 mL), upon which a precipitate formed immediately. The solid was filtered and dried under reduced pressure to give the title compound (1.18 g, 78%) as an amorphous colorless solid. MS (EI) m/e: 199.2 (M+H)+. stirring under an hydrogen atmosphere was continued for another 24 h The crude suspension was filtered over celite the filter cake thoroughly washed with methanol the filtrate was concentrated under reduced pressure upon which a precipitate formed immediately The solid was filtered dried under reduced pressure