1-[4-(2,2-Diethoxyethoxy)phenyl]cyclopropanecarboxylic acid → 1-(Benzofuran-5-yl)cyclopropanecarboxylic acid

HRID 1505096Notes

Reaction equation

C(O[CH:4](OCC)[CH2:5][O:6][C:7]1[CH:12]=[CH:11][C:10]([C:13]2([C:16]([OH:18])=[O:17])[CH2:15][CH2:14]2)=[CH:9][CH:8]=1)C>C1(C)C(C)=CC=CC=1>[O:6]1[C:7]2[CH:12]=[CH:11][C:10]([C:13]3([C:16]([OH:18])=[O:17])[CH2:15][CH2:14]3)=[CH:9][C:8]=2[CH:4]=[CH:5]1

Participants

Conditions

Temperature: 140 °C

Procedure

To a suspension of crude 1-[4-(2,2-diethoxy-ethoxy)-phenyl]-cyclopropanecarboxylic acid (20 g, ˜65 mmol) in xylene (100 mL) was added PPA (22.2 g, 64.9 mmol) at room temperature. The mixture was heated at reflux (140° C.) for 1 hour before it was cooled to room temperature and decanted from the PPA. The solvent was evaporated under vacuum to obtain the crude product, which was purified by preparative HPLC to provide 1-(benzofuran-5-yl)cyclopropanecarboxylic acid (1.5 g, 5%). 1H NMR (400 MHz, DMSO-d6) δ 12.25 (br s, 1 H), 7.95 (d, J=2.8 Hz, 1 H), 7.56 (d, J=2.0 Hz, 1 H), 7.47 (d, J=11.6 Hz, 1 H), 7.25 (dd, J=2.4, 11.2 Hz, 1 H), 6.89 (d, J=1.6 Hz, 1 H), 1.47-1.44 (m, 2 H), 1.17-1.14 (m, 2 H).

Workup

additionwas added PPA (22.2 g, 64.9 mmol) at room temperature
temperatureThe mixture was heated
temperaturewas cooled to room temperature
customdecanted from the PPA
customThe solvent was evaporated under vacuum
customto obtain the crude product, which
customwas purified by preparative HPLC

Sources & evidence

ORD record: ord-5cf07f60d325448eb2acd810b38c4011
Source dataset: uspto-grants-2015_12
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09216969B2

Reaction notes

Loading…