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

HRID 1908015Notes

Reaction equation

HRID 1908015 reaction equation
O[CH:2]=[C:3]1[C:12]2([CH2:17][CH2:16][N:15]([C:18]([O:20][CH2:21][C:22]3[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=3)=[O:19])[CH2:14][CH2:13]2)[O:11][C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[C:4]1=O.[NH2:29][NH2:30]>CCO>[N:15]1([C:18]([O:20][CH2:21][C:22]2[CH:23]=[CH:24][CH:25]=[CH:26][CH:27]=2)=[O:19])[CH2:16][CH2:17][C:12]2([C:3]3[CH:2]=[N:30][NH:29][C:4]=3[C:5]3[CH:6]=[CH:7][CH:8]=[CH:9][C:10]=3[O:11]2)[CH2:13][CH2:14]1

Participants

4

Reactant 2

HCID 9321HydrazineHCID 67463745Benzyl 3-(hydroxymethylene)-4-oxo-spiro[chromane-2,4'-piperidine]-1'-carboxylate

Product 1

HCID 58550771benzyl spiro[1H-chromeno[4,3-c]pyrazole-4,4'-piperidine]-1'-carboxylateYield 58%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A solution of benzyl 3-(hydroxymethylene)-4-oxo-spiro[chromane-2,4′-piperidine]-1′-carboxylate (1.95 g, 5.10 mmol) and hydrazine (161 μL, 5.10 mmol) in EtOH (39 mL) was stirred at room temperature for 1 hour and then at 50° C. for 3 hours. The reaction mixture was concentrated and the residue was purified by silica gel chromatography (10-100% ethyl acetate in hexane) to afford benzyl 1H-spiro[chromeno-[4,3-c]pyrazole-4,4′-piperidine]-1′-carboxylate (1.11 g, 58%). ESI-MS m/z calc. 375.2. found 376.3 (M+1)+; Retention time: 1.71 minutes (3 min run).

Workup

  1. concentrationThe reaction mixture was concentrated
  2. customthe residue was purified by silica gel chromatography (10-100% ethyl acetate in hexane)

Sources & evidence

ORD record
ord-e527dd6992164913b709681133a9b3f3
Source dataset
uspto-grants-2013_12
Patent number
US08598164B2

Reaction notes

Loading…