Ammonium formate → 9-(tert-Butyl) 2-methyl 1-oxa-4,9-diazaspiro[5.5]undecane-2,9-dicarboxylate

Participants

Reaction Conditions

Reaction Steps

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).

Provenance & Evidence