tert-Butyl (triphenylphosphoranylidene) acetate → t-Butyl 7-phenyl-2-heptenoate

HRID 1107166Notes

Reaction equation

HRID 1107166 reaction equation
[C:1]1([CH2:7][CH2:8][CH2:9][CH2:10][CH:11]=O)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[C:13]([O:17][C:18]([CH:20]=P(C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)=[O:19])([CH3:16])([CH3:15])[CH3:14]>C1COCC1>[C:1]1([CH2:7][CH2:8][CH2:9][CH2:10][CH:11]=[CH:20][C:18]([O:17][C:13]([CH3:16])([CH3:15])[CH3:14])=[O:19])[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1

Participants

4

Reactant 2

HCID 256127tert-Butyl (triphenylphosphoranylidene) acetateHCID 561886Benzenepentanal

Product 1

HCID 54541139t-Butyl 7-phenyl-2-heptenoateYield 80%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a solution of 5-phenylpentanal (60 mmol) in anhydrous THF (100 mL) at room temperature is added (t-butoxycarbonylmethylene)triphenyl-phosphorane (27.5 g, 72 mmol). The resulting orange solution is stirred for 2.5 hours, after which TLC analysis indicated complete reaction. The reaction mixture is concentrated in vacuo to afford a crude product which is chromatographed on silica gel (hexane/EtOAc, 19:1) to afford 12.4 g of t-butyl 7-phenyl-2-heptenoate (80%) as a colorless oil. TLC [pet-ether/EtOAc, 9:1, Rf (aldehyde)=0.60, Rf (ester)=0.80]. 1H NMR (300 MHz, CDCl3) δ 1.45 (s, 9H), 1.65 (m, 4H), 2.18 (q, 2H), 2.61 (t, 2H), 5.70 (d, 1H), 6.82 (dt, 1H), 7.10-7.30 (m, 5H) ppm.

Workup

  1. customreaction
  2. concentrationThe reaction mixture is concentrated in vacuo
  3. customto afford a crude product which
  4. customis chromatographed on silica gel (hexane/EtOAc, 19:1)

Sources & evidence

ORD record
ord-5d94c76fbd58440082549562f733cd6e
Source dataset
uspto-grants-2000_05
Patent number
US06057369

Reaction notes

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