4-Acetoxyconiferaldehyde → 4-Acetoxyconiferyl alcohol

HRID 61509Notes

Reaction equation

HRID 61509 reaction equation
[C:1]([O:4][C:5]1([OH:17])[CH:14]=[CH:13][C:8](/[CH:9]=[CH:10]/[CH:11]=[O:12])=[CH:7][CH:6]1[O:15][CH3:16])(=[O:3])[CH3:2]>C(Cl)Cl>[C:1]([O:4][C:5]1([OH:17])[CH:14]=[CH:13][C:8](/[CH:9]=[CH:10]/[CH2:11][OH:12])=[CH:7][CH:6]1[O:15][CH3:16])(=[O:3])[CH3:2]

Participants

3

Reactant 1

HCID 1298521484-Acetoxyconiferaldehyde

Product 1

HCID 1317371784-Acetoxyconiferyl alcoholYield 96%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

4-Acetoxyconiferaldaldehyde was prepared in 94-96% yield by acetylation of coniferaldehyde with acetic anhydride/pyridine and then reduced with borane/tert-butylamine complex to give the corresponding alcohol, as follows. The 4-acetoxyconiferaldehyde was dissolved in methylene chloride to which borane/tert-butylamine complex (1.5 equiv) was added. The mixture was stirred at room temperature for 2 h, when TLC showed that the starting material had disappeared completely. The solvent was evaporated at 40° C. under reduced pressure. The residue was hydrolyzed with 0.5 M H2SO4 in ethanol/water (1:1) for 1.5 h. Most of the ethanol was removed by evaporation, and the product was extracted with ethyl acetate. The ethyl acetate solution was washed with saturated NH4Cl and dried over MgSO4. Evaporation of the ethyl acetate gave the product, 4-acetoxyconiferyl alcohol as a pale yellow oil (96% yield); 1H NMR (acetone-d6) δ 2.31 (3H, s, OAc), 3.83 (3H, s, OAc), 3.90 (1H, t, J) 5.5 Hz, γ-OH), 4.22 (2H, dt, J) 5.5, 1.7 Hz, γ), 6.38 (1H, dt, J) 15.9, 5.2 Hz, β), 6.58 (1H, dt, J=15.9, 1.7 Hz, α), 6.97 (2H, m, A5/6), 7.15 (s, 1H, A2); 13C NMR δ 20.5 (OAc), 56.2 (OMe), 63.1 (γ), 110.9 (A2), 119.5 (A6), 123.6 (A5), 129.3 (α), 131.4 (β), 137.2 (A1), 140.2 (A4), 152.3 (A3), 169.0 (OAc).

Workup

  1. additionwas added
  2. customThe solvent was evaporated at 40° C. under reduced pressure
  3. waitThe residue was hydrolyzed with 0.5 M H2SO4 in ethanol/water (1:1) for 1.5 h
  4. customMost of the ethanol was removed by evaporation
  5. extractionthe product was extracted with ethyl acetate
  6. washThe ethyl acetate solution was washed with saturated NH4Cl
  7. dry with materialdried over MgSO4
  8. customEvaporation of the ethyl acetate

Sources & evidence

ORD record
ord-c48176f023f64bec83acb69459ba5313
Source dataset
uspto-grants-2016_09
Patent number
US09441235B2

Reaction notes

Loading…