Hydroxyphenylacetic acid → (4-Hydroxyphenyl)propanedioic acid

HRID 225308Notes

Reaction equation

[OH:1][C:2]1[CH:7]=[CH:6][C:5]([CH2:8][C:9]([OH:11])=[O:10])=[CH:4][CH:3]=1.C([N-]C(C)C)(C)C.[Li+].Cl[C:21]([O:23]CC)=[O:22].Cl>O1CCCC1.O>[C:9]([CH:8]([C:5]1[CH:4]=[CH:3][C:2]([OH:1])=[CH:7][CH:6]=1)[C:21]([OH:23])=[O:22])([OH:11])=[O:10]

Participants

Conditions

Temperature: -40 °C

Procedure

About 0.5 mole of 4-hydroxybenzeneacetic acid is dissolved in about 50 ml of anhydrous tetrahydrofuran at -40° C. To this solution is added 3 equivalents of lithium diisopropylamide. The temperature is maintained at about -40° C. for about 15 minutes. Then 1 equivalent of ethyl chloroformate is added and the temperature is raised from about -40° C. to about 20° C. and the reaction mixture stirred for about 60 minutes. The reaction mixture is poured into water and the monoester of α-carboxy-4-hydroxybenzeneacetic acid is recovered from the aqueous solution. Hydrolysis of the half-ester with sodium hydroxide followed by acidification with hydrochloric acid gives α-carboxy-4-hydroxybenzeneacetic acid.

Workup

temperaturethe temperature is raised from about -40° C. to about 20° C.
customthe monoester of α-carboxy-4-hydroxybenzeneacetic acid is recovered from the aqueous solution
customHydrolysis of the half-ester with sodium hydroxide

Sources & evidence

ORD record: ord-0bc7f58608de4eb5aca2ae5cb0e970a4
Source dataset: uspto-grants-1980_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US04236002

Reaction notes

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