1-(Triphenylphosphoranylidene)acetone → 1-(N-Cbz-2-pyrrolidinyl)-1-buten-3-one

HRID 440096

Reaction equation

HRID 440096 reaction equation
[C:1]([N:11]1[CH2:17][CH2:16][CH2:15][C@H:12]1[CH:13]=O)([O:3][CH2:4][C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=1)=[O:2].C1(P(C2C=CC=CC=2)(C2C=CC=CC=2)=[CH:25][C:26](=[O:28])[CH3:27])C=CC=CC=1>C1C=CC=CC=1>[C:1]([N:11]1[CH2:17][CH2:16][CH2:15][CH:12]1[CH:13]=[CH:25][C:26](=[O:28])[CH3:27])([O:3][CH2:4][C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=1)=[O:2]

Participants

4

Reactant 2

HCID 150381-(Triphenylphosphoranylidene)acetoneHCID 11746545(S)-2-Formyl-pyrrolidine-1-carboxylic acid benzyl ester

Product 1

HCID 572702461-(N-Cbz-2-pyrrolidinyl)-1-buten-3-oneYield 69%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

To a stirred solution of N-Cbz-L-prolinal (6.3 g, 27 mmol, from step 24d above) in 30 mL of benzene was added 9.42 g (29.6 mmol) of 1-triphenylphosphoranylidene-2-propanone (Aldrich) at room temperature. The reaction mixture was heated to reflux for 4 hr. The benzene was removed under vacuum, and the residue was dissolved in ether and cooled for 16 hr. The phosphine oxide by product was removed by filtration, and the solution was further purified by column chromatography on silica gel, eluting with 20% ethyl acetate in hexanes, to afford 4.4 g of the title product (69% yield).

Workup

  1. temperatureThe reaction mixture was heated
  2. temperatureto reflux for 4 hr
  3. customThe benzene was removed under vacuum
  4. dissolutionthe residue was dissolved in ether
  5. temperaturecooled for 16 hr
  6. customThe phosphine oxide by product was removed by filtration
  7. customthe solution was further purified by column chromatography on silica gel
  8. washeluting with 20% ethyl acetate in hexanes

Sources & evidence

ORD record
ord-fd7d853d1ad9403c8c3b1b2c8e4ceed7
Source dataset
uspto-grants-1996_05
Patent number
US05516912

Linked notes

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