Dichloromethane → (S)-5-oxo-1-(phenylmethyl)-2-pyrrolidineacetaldehyde

HRID 2050940Notes

Reaction equation

HRID 2050940 reaction equation
[C:1]1([CH2:7][N:8]2[C@H:12]([CH2:13][CH:14]=C)[CH2:11][CH2:10][C:9]2=[O:16])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C(Cl)Cl.[O:20]=[O+][O-]>CO>[O:16]=[C:9]1[N:8]([CH2:7][C:1]2[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=2)[C@H:12]([CH2:13][CH:14]=[O:20])[CH2:11][CH2:10]1

Participants

5

Reactant 3

HCID 6344DichloromethaneHCID 24823OzoneHCID 10398365(S)-1-(phenylmethyl)-5-(2-propenyl)-2-pyrrolidinone

Product 1

HCID 10330963(S)-5-oxo-1-(phenylmethyl)-2-pyrrolidineacetaldehyde

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A solution of (S)-1-(phenylmethyl)-5-(2-propenyl)-2-pyrrolidinone (44.8 g, 0.208 mol) in 800 mL of 1:1 methanol:methylene chloride was cooled to -78° C. and was ozonized using a Welsbach ozonizer for 6.5 h, approximately 1 h longer than the time required to observe a light blue color of ozone in the solution. Excess ozone was flushed out of the system with oxygen, and the solution was treated with methyl sulfide (80 mL). The solution was then allowed to come to room temperature and to stand overnight. The solvents were removed on a rotary evaporator, and the residual liquid was dissolved in 700 mL of methylene chloride, washed with water, and dried over Na2SO4. Evaporation of the solvent afforded 43.0 g of crude (S)-5-oxo-1-(phenylmethyl)-2-pyrrolidineacetaldehyde. Chromatography on silica gel (1 kg) eluting with 4% methanol in methylene chloride afforded 38 g (84.4% yield) of the pure (S)-5-oxo-1-(phenylmethyl)-2-pyrrolidineacetaldehyde. 1H NMR (CDCl3) δ 1.60-2.60 (m, 4 H, CH2), 2.77 (half of ABX, 1 H, Jgem =18,Jvic =4 Hz, CH2CHO), 3.98 (m, 1 H, NCH), 4.10 and 4.82 (AB, 2 H,Jgem =15 Hz, CH2Ph), 7.15-7.40 (m, 5 H, phenyl), 9.65 (s, 1 H, CHO).

Workup

  1. customfor 6.5 h
  2. customapproximately 1 h
  3. customExcess ozone was flushed out of the system with oxygen
  4. additionthe solution was treated with methyl sulfide (80 mL)
  5. customto come to room temperature
  6. customThe solvents were removed on a rotary evaporator
  7. dissolutionthe residual liquid was dissolved in 700 mL of methylene chloride
  8. washwashed with water
  9. dry with materialdried over Na2SO4
  10. customEvaporation of the solvent

Sources & evidence

ORD record
ord-98c539ecfe8d4418b5ba64aef940bcdd
Source dataset
uspto-grants-1991_05
Patent number
US05015653

Reaction notes

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