Reaction #160055

Reaction equation

9-tert-butyl 2-methyl 4-benzyl-1-oxa-4,9-diazaspiro[5.5]undecane-2,9-dicarboxylate

ammonium formate

→

9-tert-butyl 2-methyl 1-oxa-4,9-diazaspiro[5.5]undecane-2,9-dicarboxylate

Yield 74.0%

Solvents

EtOH

Conditions

Workup

1. 1
   TemperatureThe reaction mixture was cooled to room temperature
2. 2
   Filtrationfiltered
3. 3
   Otherpartitioned between EtOAc/1M aq. NaOH
4. 4
   OtherThe layers were separated
5. 5
   Dryingthe organic layer was dried over Na2SO4
6. 6
   Filtrationfiltered
7. 7
   Concentrationconcentrated in vacuo

Procedure

A mixture of 9-tert-butyl 2-methyl 4-benzyl-1-oxa-4,9-diazaspiro[5.5]undecane-2,9-dicarboxylate (670 mg, 1.66 mmol), ammonium formate (623 mg, 9.936 mmol) and palladium, 10 wt. % on activated carbon (353 mg, 3.31 mmol) in EtOH (5 mL) was heated at 65° C. for 50 minutes. The reaction mixture was cooled to room temperature, filtered and partitioned between EtOAc/1M aq. NaOH. The layers were separated and the organic layer was dried over Na2SO4, filtered and concentrated in vacuo to yield 9-tert-butyl 2-methyl 1-oxa-4,9-diazaspiro[5.5]undecane-2,9-dicarboxylate as a foam (386 mg, 74%). ESI-MS m/z calc. 314.2. Found 315.5 (M+1); Retention time: 0.99 minutes (3 min run).

Source