Water → 3-Bromo-2-methyl-6-methylsulfonylbenzaldoxime
Reaction equation
[N:1](OCCCC)=[O:2].[CH3:8][C:9]1[C:14]([CH3:15])=[C:13]([S:16]([CH3:19])(=[O:18])=[O:17])[CH:12]=[CH:11][C:10]=1[Br:20].CC(C)([O-])C.[K+].O>CN(C)C=O.C(O)(=O)C>[Br:20][C:10]1[C:9]([CH3:8])=[C:14]([C:13]([S:16]([CH3:19])(=[O:17])=[O:18])=[CH:12][CH:11]=1)[CH:15]=[N:1][OH:2]Participants
Procedure
A solution of 2.1 g (20 mmol) of n-butyl nitrite (97%) and 4 g (15 mmol) of 2,3-dimethyl-4-methylsulfonylbromobenzene in 50 ml of dimethylformamide is cooled to from −55 to −60° C., and a solution of 2.8 g (25 mmol) of potassium tert-butoxide in 35 ml of dimethylformamide is added dropwise at this temperature, over a period of 20 minutes. The reaction is monitored by HPLC. For work-up, initially 10 ml of water are added, and the mixture is then adjusted to pH 5-6 using about 9 ml of glacial acetic acid. The mixture is then poured onto 100 ml of ice-water and the aqueous phase is extracted with methylene chloride. The organic phase is washed with sodium bicarbonate solution, dried over magnesium sulfate and concentrated. This gives 3.6 g of an oily crude product (90% by HPLC) which can be purified by recrystallization from toluene.
Workup
- extractionthe aqueous phase is extracted with methylene chloride
- washThe organic phase is washed with sodium bicarbonate solution
- dry with materialdried over magnesium sulfate
- concentrationconcentrated
- customThis gives 3.6 g of an oily crude product (90% by HPLC) which can be purified by recrystallization from toluene
Sources & evidence
- ORD record
- ord-79dccc92741440fabe23d9841aea8b13
- Source dataset
- uspto-grants-2007_12
- Patent number
- US07309802B2
Reaction notes
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