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

Participants

Reaction Steps

A mixture of benzyl spiro[1H-chromeno[4,3-c]pyrazole-4,4′-piperidine]-1′-carboxylate (1.11 g, 2.96 mmol) and palladium (10% wt on carbon, 157 mg, 0.15 mmol) in MeOH (15 mL) was set under hydrogen (1 atm) and stirred vigorously at room temperature for 3 hours. The reaction mixture was filtered through Celite and the filtrate was concentrated to afford 1H-spiro[chromeno[4,3-c]pyrazole-4,4′-piperidine] (570 mg, 80%). ESI-MS m/z calc. 241.1. found 242.5 (M+1)+; Retention time: 0.42 minutes (3 min run).

Provenance & Evidence