Ethyl Bromide → 4-Methoxyimino-5-methyl-6-bromothiochroman

HRID 1292504

Reaction equation

HRID 1292504 reaction equation
[Mg].[CH2:2]([Br:4])[CH3:3].[CH3:5][O:6][N:7]=[C:8]1[C:17]2[C:12](=[CH:13]C=[C:15](C3C=NN(CC)C=3OS(CCC)(=O)=O)[C:16]=2C)[S:11](=O)(=O)[C:10](=C=O)[CH2:9]1>C1COCC1>[CH3:5][O:6][N:7]=[C:8]1[C:17]2[C:12](=[CH:13][CH:3]=[C:2]([Br:4])[C:16]=2[CH3:15])[S:11][CH2:10][CH2:9]1

Participants

5

Reactant 3

HCID 6332Ethyl BromideHCID 5462224MagnesiumHCID 867526644-Methoxyimino-5-methyl-6-(1-ethyl-5-n-propanesulfonyloxypyrazol-4-yl)-carbonylthiochroman-1,1-dioxide

Product 1

HCID 543825024-Methoxyimino-5-methyl-6-bromothiochroman

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

1.1 Grams (46 mmol) of magnesium was dispersed in 10 ml of THF, and 2.2 g (20 mmol) of ethyl bromide was dropwise added under nitrogen current. The mixture was allowed to react for 10 minutes, and then a THF solution of 2.9 g (10 mmol) of the 4-methoxyimino-5-methyl-6-bromothiochroman obtained in the above (1) was gradually added at room temperature. The mixture was refluxed for 3 hours and then cooled to room temperature, and carbon dioxide gas was bubbled in for 1 hour. To the reaction mixture was added 5% hydrochloric acid, and the mixture was extracted with ether. An ether layer was extracted with a 5% potassium carbonate aqueous solution, and an aqueous layer was neutralized with concentrated hydrochloric acid. The neutralization product was extracted with ethyl acetate, and the extract was washed with a saturated sodium chloride aqueous solution. The washed extract was dried over sodium sulfate, and then the solvent was distilled off to give 1.6 g (yield 63%) of 4-methoxyimino-5-methylthiochroman-6-carboxylic acid.

Workup

  1. customto react for 10 minutes

Sources & evidence

ORD record
ord-6af1fb0950344ef19641359dc4c23735
Source dataset
uspto-grants-1998_05
Patent number
US05756759

Linked notes

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