Ethyl diazoacetate → Ethyl 5-benzyl-4,6-dioxo-1,3a,4,5,6,6a-hexahydropyrrolo[3,4-c]pyrazole-3-carboxylate

HRID 484205

Reaction equation

HRID 484205 reaction equation
[N+:1](=[CH:3][C:4]([O:6][CH2:7][CH3:8])=[O:5])=[N-:2].[CH2:9]([N:16]1[C:20](=[O:21])[CH:19]=[CH:18][C:17]1=[O:22])[C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1>C(OCC)C>[CH2:9]([N:16]1[C:20](=[O:21])[CH:19]2[CH:18]([NH:2][N:1]=[C:3]2[C:4]([O:6][CH2:7][CH3:8])=[O:5])[C:17]1=[O:22])[C:10]1[CH:11]=[CH:12][CH:13]=[CH:14][CH:15]=1

Participants

4

Reactant 2

HCID 12192Ethyl diazoacetateHCID 74204Benzylmaleimide

Product 1

HCID 2857138Ethyl 5-benzyl-4,6-dioxo-1,3a,4,5,6,6a-hexahydropyrrolo[3,4-c]pyrazole-3-carboxylateYield 100%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent2×

Procedure

Ethyl diazoacetate (13 g, 114 mmol) in diethyl ether (100 ml) was added dropwise to a solution of N-benzylmaleimide (10 g, 53 mmol) in diethyl ether (250 ml). The resulting mixture was allowed to stir for 18 hours; the solvent was then removed in vacuo, and the resulting residue partitioned between methylene chloride and water. The organic layer was dried over sodium sulfate, filtered and concentrated to provide the title product as a white solid, mp 145°-146° with decomposition (16 g, 53 mmol, 100% yield). 1H NMR (CDCl3): 7.31 (m, 5H), 7.02 (bs, 1H), 4.89 (dd, J=11, 2 Hz, 1H), 4.65 (s, 2H), 4.55 (d, J=10 Hz, 1H), 4.36 (q, J=7 Hz, 2H), 1.37 (t, J=7 Hz, 3H).

Workup

  1. customthe solvent was then removed in vacuo
  2. customthe resulting residue partitioned between methylene chloride and water
  3. dry with materialThe organic layer was dried over sodium sulfate
  4. filtrationfiltered
  5. concentrationconcentrated

Sources & evidence

ORD record
ord-2896b0a134f44d52bb1ff402d223cf2d
Source dataset
uspto-grants-1993_07
Patent number
US05229396

Linked notes

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