Ethanol → 2,5-Dithien-2-ylterephthalic acid

HRID 1473806Notes

Reaction equation

[OH-].[Na+].C(O)C.C[O:7][C:8](=[O:29])[C:9]1[CH:18]=[C:17]([C:19]2[S:20][CH:21]=[CH:22][CH:23]=2)[C:12]([C:13]([O:15]C)=[O:14])=[CH:11][C:10]=1[C:24]1[S:25][CH:26]=[CH:27][CH:28]=1>O>[S:20]1[CH:21]=[CH:22][CH:23]=[C:19]1[C:17]1[CH:18]=[C:9]([C:8]([OH:29])=[O:7])[C:10]([C:24]2[S:25][CH:26]=[CH:27][CH:28]=2)=[CH:11][C:12]=1[C:13]([OH:15])=[O:14]

Participants

Conditions

Temperature: 78 °C

Procedure

Sodium hydroxide (4.80 g, 120.0 mmol) is dissolved in water (30 cm3), then ethanol (250 cm3) and 2,5-dithien-2-ylterephthalic acid dimethyl ester (5.30 g, 14.8 mmol) are added. This mixture is heated at 78° C. overnight. The solvent is evaporated under reduced pressure to about half of original volume then water is added. The resultant mixture is neutralized with concentrated hydrochloric acid. The precipitate is collected by filtration and washed with water and ethanol, then dried in vacuo, to yield the product as an off-white solid (4.13 g, 84%). 1H NMR (300 MHz, DMSO-d6): δ(ppm) 13.46 (s, 2H, COOH), 7.72 (s, 2H, Ar—H), 7.70 (dd, J=5.1 and 1.1 Hz, 2H, Ar—H), 7.28 (dd, J=3.6 and 1.1 Hz, 2H, Ar—H), 7.17 (m, 2H, Ar—H); 13C NMR (75 MHz, DMSO-d6): δ(ppm) 168.7 (C═O), 139.7 (q), 134.5 (q), 131.4 (q), 130.2 (CH), 127.9 (CH), 127.5 (CH), 127.1 (CH).

Workup

customThe solvent is evaporated under reduced pressure to about half of original volume
additionwater is added
filtrationThe precipitate is collected by filtration
washwashed with water and ethanol
customdried in vacuo

Sources & evidence

ORD record: ord-efbf3843160a414eae5d4ecbf033a4bb
Source dataset: uspto-grants-2015_04
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09017577B2

Reaction notes

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