Reaktion #77954

Reaktionsgleichung

water

n-butyl nitrite

2,3-dimethyl-4-methylsulfonylbromobenzene

potassium tert-butoxide

→

3-bromo-2-methyl-6-methylsulfonylbenzaldoxime

Lösungsmittel

acetic acid

dimethylformamide

dimethylformamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionthe aqueous phase is extracted with methylene chloride
2. 2
   WaschenThe organic phase is washed with sodium bicarbonate solution
3. 3
   Trocknendried over magnesium sulfate
4. 4
   Einengenconcentrated
5. 5
   SonstigeThis gives 3.6 g of an oily crude product (90% pure according to HPLC) which can be purified by recrystallization from toluene

Vorschrift

A solution of 2.1 g (20 mmol) of n-butyl nitrite (97%) pure 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 pH is subsequently adjusted to 5-6 using approximately 9 ml of glacial acetic acid. The reaction mixture is subsequently poured into 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% pure according to HPLC) which can be purified by recrystallization from toluene.

Quelle