Water → Benzofuran-2,3-dione2-{o-[2-(tetrahydropyran-2-yloxy)-ethyl]-oxime}

HRID 1858142Notes

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].C[O-].[Na+].Br[CH2:17][CH2:18][O:19][CH:20]1[CH2:25][CH2:24][CH2:23][CH2:22][O:21]1.O>CO>[O:21]1[CH2:22][CH2:23][CH2:24][CH2:25][CH:20]1[O:19][CH2:18][CH2:17][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: 20 °C

Procedure

5 g (0.03 mol) of benzofuran-2,3-dione 2-oxime (XI-1) are dissolved in 30 ml of methanol, and at 20° C. 15 ml of a 2 molar solution of sodium methoxide in methanol are added dropwise. The solvent is distilled off under reduced pressure. The crystalline residue is dissolved in 30 ml of N-methyl-2-pyrrolidinone and treated with 6.27 g (0.03 mol) of 2-(2-bromoethoxy)-tetrahydropyran at 20° C. The reaction mixture is stirred for 16 hours at 20° C., poured into 100 ml of water and the resulting mixture is extracted twice with 100 ml of dichloromethane each time. The solvent is distilled off under reduced pressure and the residue is chromatographed over silica gel using a mixture of diethyl ether/dichloromethane/petroleum ether (1:1:2). 5.55 g (62.1% of theory) of benzofuran-2,3-dione 2-{O-[2-(tetrahydropyran-2-yloxy)-ethyl]-oxime} (XIV-2) are obtained.

Workup

customat 20° C
distillationThe solvent is distilled off under reduced pressure
dissolutionThe crystalline residue is dissolved in 30 ml of N-methyl-2-pyrrolidinone
extractionthe resulting mixture is extracted twice with 100 ml of dichloromethane each time
distillationThe solvent is distilled off under reduced pressure
customthe residue is chromatographed over silica gel using
additiona mixture of diethyl ether/dichloromethane/petroleum ether (1:1:2)

Sources & evidence

ORD record: ord-b079f36f6f384594828f9f54c71fe37b
Source dataset: uspto-grants-2000_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06150521

Reaction notes

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