Acetic acid, 2-(triphenylphosphoranylidene)-, methyl ester → Methyl 2-(6-hydroxy-1-benzofuran-3-yl)acetate

HRID 1947475Notes

Reaction equation

[OH:1][C:2]1[CH:11]=[CH:10][C:5]2[C:6](=O)[CH2:7][O:8][C:4]=2[CH:3]=1.C1(P(=[CH:31][C:32]([O:34][CH3:35])=[O:33])(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>C1(C)C(C)=CC=CC=1>[CH3:35][O:34][C:32](=[O:33])[CH2:31][C:6]1[C:5]2[CH:10]=[CH:11][C:2]([OH:1])=[CH:3][C:4]=2[O:8][CH:7]=1

Participants

Conditions

Temperature: 120 °C

Procedure

To a suspension of 6-hydroxy-benzofuran-3-one (5.0 g, 33.3 mmol) in xylene (100 mL) was added methyl (triphenylphosphoranylidene)acetate (11.1 g, 33.3 mmol) and the resulting reaction mixture was heated (120° C., 24 h). The reaction mixture was concentrated in vacuo and the residue was treated with 1 M HCl adjusting the pH to 3. The organic layer was extracted with EtOAc (2×100 mL). The combined organic layers were dried, filtered and concentrated in vacuo. The resulting residue was purified by silica gel flash chromatography using EtOAc:hexane (0-70%) to provide the title compound as a clear oil (1.6 g, 23%). MS (ESI): mass calcd. for C10H10NO4, 206.2; m/z found, 207.2 [M+H]+. 1H NMR (400 MHz, CDCl3): 7.03-7.07 (m, 1H), 7.37 (d, J=8.4, 1H), 6.93 (d, J=2.2, 1H), 6.77 (dd, J=8.4, 2.2, 1H), 5.20 (br s, 1H), 3.74 (s, 3H), 3.67 (s, 2H).

Workup

customthe resulting reaction mixture
concentrationThe reaction mixture was concentrated in vacuo
additionthe residue was treated with 1 M HCl adjusting the pH to 3
extractionThe organic layer was extracted with EtOAc (2×100 mL)
customThe combined organic layers were dried
filtrationfiltered
concentrationconcentrated in vacuo
customThe resulting residue was purified by silica gel flash chromatography

Sources & evidence

ORD record: ord-4352966221b2499fa06fdc7a5a79f051
Source dataset: uspto-grants-2013_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08399465B2

Reaction notes

Loading…