Water → Benzofuran-2,3-dione2-[o-(2-hydroxy-ethyl)-oxime]

HRID 1858133Notes

Reaction equation

[O:1]1[C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][C:4]=2[C:3](=[O:10])[C:2]1=[N:11][OH:12].[H-].[Na+].Br[CH2:16][CH2:17][OH:18].O>CN(C)C=O>[OH:18][CH2:17][CH2:16][O:12][N:11]=[C:2]1[C:3](=[O:10])[C:4]2[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=2[O:1]1

Participants

Conditions

Temperature: 0 °C

Procedure

11.8 g (0.0725 mol) of benzofuran-2,3-dione 2-oxime (XI-1) (Stoermer, Kahlert, B. 35, 1644) are dissolved in 75 ml of dimethylformamide. With cooling, 3 g (0.075 mol) of 60% strength sodium hydride (mineral oil suspension) are added a little at a time and stirring is continued at a temperature of 25° C. for about one hour until the formation of gas has ceased. The mixture is then cooled to 0° C., and at this temperature 9.3 g (0.0744 mol) of 2-bromoethanol are added dropwise and stirring is continued at 25° C. for a further 24 hours. The reaction mixture is poured into water and the resulting mixture is extracted with ethyl acetate, the organic phase is dried over sodium sulphate and the solvent is distilled off under reduced pressure. The residue is recrystallized from a mixture of 150 ml of toluene and 100 ml of cyclohexane. 11.5 g (64% of theory) of benzofuran-2,3-dione 2-[O-(2-hydroxy-ethyl)-oxime] (VII-1) are obtained (content according to HPLC analysis: 83.5%). A sample recrystallized from toluenes has a melting point of 110-111° C.

Workup

temperatureWith cooling
stirringstirring
waitis continued at 25° C. for a further 24 hours
extractionthe resulting mixture is extracted with ethyl acetate
dry with materialthe organic phase is dried over sodium sulphate
distillationthe solvent is distilled off under reduced pressure
customThe residue is recrystallized from a mixture of 150 ml of toluene and 100 ml of cyclohexane

Sources & evidence

ORD record: ord-4a18010b764046f891067a714fac9266
Source dataset: uspto-grants-2000_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06150521

Reaction notes

Loading…