benzyl 1-ethyl-1H-spiro[chromeno[4,3-c]pyrazole-4,4'-piperidine]-1'-carboxylate → 1-ethyl-1H-spiro[chromeno[4,3-c]pyrazole-4,4'-piperidine]

Participants

Reaction Steps

Benzyl 1-ethyl-1H-spiro[chromeno[4,3-c]pyrazole-4,4′-piperidine]-1′-carboxylate (530 mg, 1.3 mmol) was stirred in methanol (9.5 mL) with Pd/C (70 mg, 0.070 mmol) under a balloon of hydrogen for 16 h. The reaction was filtered through a syringe filter and the solvent evaporated to give 1-ethyl-1H-spiro[chromeno[4,3-c]pyrazole-4,4′-piperidine] (350 mg, 99%). ESI-MS m/z calc. 269.2. found 270.5 (M+1)+; Retention time: 0.80 minutes (3 min run).

Provenance & Evidence