Acetic Acid → HCID 15925659, compound

HRID 1591245Notes

Reaction equation

HRID 1591245 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:12][CH:11]=[C:10]([C:13]([O-:15])=[O:14])[NH:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].[C:16](O)(=O)[CH3:17]>[Zn]>[C:1]([O:5][C:6]([N:8]1[CH2:12][CH2:11][CH:10]([C:13]([O:15][CH2:16][CH3:17])=[O:14])[NH:9]1)=[O:7])([CH3:4])([CH3:2])[CH3:3]

Participants

4

Reactant 2

HCID 176Acetic AcidHCID 86746760HCID 86746760, compound

Product 1

HCID 15925659HCID 15925659, compound

Reagents, catalysts & solvents 1

HCID 23994ZincCatalyst

Procedure

53.5 g of Diazald® in 750 ml of tert.-butyl methyl ether are cooled to 0° C., and 16.5 g of KOH dissolved in 250 ml of ethanol/water (9:1) are added. The mixture is warmed to room temperature and stirred at room temperature for 1 h. 25.0 g (0.25 mol) ethyl acrylate in 20 ml of tert.-butyl methyl ether are added dropwise over 1.5 h, with 40 ml of water being added towards the end. For the working up, 800 ml of diethyl ether are added, and the organic phase is separated off, washed with saturated NaCl solution and dried over Na2SO4. The residue is dissolved in 500 ml of DMF, and 55 ml of triethylamine, 100 mg of N,N-dimethylaminopyridine and 54 g (0.25 mol) of di-tert.-butyl pyrocarbonate are added. Chromatography on silica gel results in 8 g of ethyl Δ2 -1-tert.-butoxycarbonylpyrazoline-3-carboxylate. 6 g of the pyrazoline derivatives are dissolved in 100 ml of acetic acid, and 7 g of zinc powder are added and stirred. The reaction solution is removed by filtration after 2 h, the filtrate is evaporated in a rotary evaporator, and the residue is chromatographed on silica gel. 4.5 g of ethyl 1-tert.-butoxycarbonylpyrazolidine-3-carboxylate are obtained.

Workup

  1. customThe reaction solution is removed by filtration after 2 h
  2. customthe filtrate is evaporated in a rotary evaporator
  3. customthe residue is chromatographed on silica gel

Sources & evidence

ORD record
ord-b24a3ea8ac3c4843bc767d1c9064c0f5
Source dataset
uspto-grants-1993_04
Patent number
US05206343

Reaction notes

Loading…