Triphenylphosphine → 4'-Ethoxycarbonyl-methoxy-3',5'-dimethoxyacetophenone

HRID 1792976Notes

Reaction equation

HRID 1792976 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([C:12](=[O:14])[CH3:13])[CH:6]=[C:7]([O:10][CH3:11])[C:8]=1O.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[C:34]([O:38][CH2:39][CH3:40])(=[O:37])CO.C[CH2:42][O:43]C(/N=N/C(OCC)=O)=O>O1CCCC1>[CH2:39]([O:38][C:34]([C:8]1[C:7]([O:10][CH3:11])=[CH:6][C:5]([C:12](=[O:14])[CH2:13][O:43][CH3:42])=[CH:4][C:3]=1[O:2][CH3:1])=[O:37])[CH3:40]

Participants

6

Reactant 4

HCID 11776TriphenylphosphineHCID 12184Ethyl GlycolateHCID 17198AcetosyringoneHCID 5462977Diethyl azodicarboxylate

Product 1

HCID 220255854'-Ethoxycarbonyl-methoxy-3',5'-dimethoxyacetophenoneYield 35.9%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

Ex-61A: 3′,5′-Dimethoxy-4′-hydroxyacetophenone (6.03 g, 31 mmol) and triphenylphosphine (8.05 g, 31 mmol) were stirred in 124 mL of tetrahydrofuran (THF). The mixture was treated with ethyl glycolate (3.2 g, 31 mmol) and diethylazodicarboxylate (4.83 mL, 31 mmol). The reaction mixture was stirred under reflux for about 3.5 h and then evaporated. The residue was crystallized from hexane/ethyl acetate. The mother liquor was concentrated to give a crude product which was purified by recrystallization from EtOH twice to give 3.14 g of 4′-ethoxycarbonyl-methoxy-3′,5′-dimethoxyacetophenone. Solvent removal from the mother liquor provided additional crude product which was purified by silica gel chromatography (hexane/ethyl acetate, 1:1) to give additional product (4.2 g). The total amount of pure material isolated was 7.34 g (90% yield). mp. 81-83° C.; Anal. Calcd. for Cl4H18O6: C, 59.57; H, 6.43; Found: C, 59.60; H, 6.34; MS (direct probe): Calcd for Cl4H18O6: m/z=282, found: m/z=282.

Workup

  1. temperatureunder reflux for about 3.5 h
  2. customevaporated
  3. customThe residue was crystallized from hexane/ethyl acetate
  4. concentrationThe mother liquor was concentrated
  5. customto give a crude product which
  6. customwas purified by recrystallization from EtOH twice

Sources & evidence

ORD record
ord-1a6cab735b784644a4361ba81a9aa295
Source dataset
uspto-grants-2006_07
Patent number
US07078431B2

Reaction notes

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