Water → 3-(2-(1-Methylimidazol-5-yl)-1,3-dithian-2-yl)butyrolactone

HRID 1646689Notes

Reaction equation

[S:1]1[CH2:6][CH2:5][CH2:4][S:3][CH:2]1[C:7]1[N:11]([CH3:12])[CH:10]=[N:9][CH:8]=1.[Li]CCCC.[C:18]1(=[O:23])[O:22][CH2:21][CH:20]=[CH:19]1.O>O1CCCC1.CCCCCC.C(O)(=O)C>[CH3:12][N:11]1[C:7]([C:2]2([CH:20]3[CH2:21][O:22][C:18](=[O:23])[CH2:19]3)[S:3][CH2:4][CH2:5][CH2:6][S:1]2)=[CH:8][N:9]=[CH:10]1

Participants

Conditions

Temperature: -78 °C

Procedure

6.9 g (40 mmol) of 5-(1,3-dithian-2-yl)-1-methylimidazole are dissolved in 190 ml of tetrahydrofuran and cooled to -78° C. 40 mmol of n-BuLi in 24 ml of hexane are added dropwise to this and, after 30 minutes, at -78° C., 3.8 ml (54 mmol) of γ-crotonolactone are added. After a further 1.5 hours at -78° C., 190 ml of water are added dropwise, and the mixture is warmed to room temperature. It is subsequently acidified with glacial acetic acid, the organic layer is separated off, and the aqueous phase is washed several times with ethyl acetate. The combined organic extracts are dried over magnesium sulfate and subsequently concentrated in vacuo. The residue is chromatographed on silica gel with dichloromethane/methanol (9:1). 3.1 g (10.9 mmol, 27%) of 3-(2-(1-methylimidazol-5-yl)-1,3-dithian-2-yl)butyrolactone are obtained as a yellow oil in this way.

Workup

temperaturethe mixture is warmed to room temperature
customthe organic layer is separated off
washthe aqueous phase is washed several times with ethyl acetate
dry with materialThe combined organic extracts are dried over magnesium sulfate
concentrationsubsequently concentrated in vacuo
customThe residue is chromatographed on silica gel with dichloromethane/methanol (9:1)

Sources & evidence

ORD record: ord-d2e9efdc678545a3bd715fb2c4506cd7
Source dataset: uspto-grants-1993_01
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05180837

Reaction notes

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