Reaktion #339087

Reaktionsgleichung

2-amino-5-chloro-3-methylbenzoic acid

3-bromo-1-(3-chloro-2-pyridinyl)-1H-pyrazole-5-carboxylic acid

acetonitrile

methanesulfonyl chloride

methanesulfonyl chloride

→

2-[3-bromo-1-(3-chloro-2-pyridinyl)-1H-pyrazol-5-yl]-6-chloro-8-methyl-4H-3,1-benzoxazine-4-one

Ausbeute 14.9%

Lösungsmittel

triethylamine

triethylamine

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe mixture was stirred at room temperature for 20 minutes
2. 2
   workup.STIRRINGAfter the mixture was stirred at room temperature for 20 minutes
3. 3
   workup.STIRRINGthe mixture was stirred at room temperature for 16 hours
4. 4
   FiltrationThe reaction mixture was filtered
5. 5
   Waschenthe filter cake was washed with methyl tert-butyl ether
6. 6
   FiltrationThe resulting filter cake
7. 7
   workup.DISSOLUTIONwas dissolved in ethyl acetate
8. 8
   Waschenwashed successively with water
9. 9
   Trocknenan aqueous saturated sodium chloride solution, dried over anhydrous magnesium sulfate
10. 10
    Einengenconcentrated under reduced pressure

Vorschrift

To a mixture of 0.44 g of 3-bromo-1-(3-chloro-2-pyridinyl)-1H-pyrazole-5-carboxylic acid, 6 ml of acetonitrile and 0.20 g of triethylamine was added 0.125 ml of methanesulfonyl chloride. After the resulting mixture was stirred at room temperature for 15 minutes, 0.27 g of 2-amino-5-chloro-3-methylbenzoic acid was added and the mixture was stirred at room temperature for 20 minutes. To the mixture, 0.40 ml of triethylamine was added. After the mixture was stirred at room temperature for 20 minutes, 0.13 ml of methanesulfonyl chloride was added and the mixture was stirred at room temperature for 16 hours. The reaction mixture was filtered and the filter cake was washed with methyl tert-butyl ether. The resulting filter cake was dissolved in ethyl acetate, washed successively with water and an aqueous saturated sodium chloride solution, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure to obtain 0.098 g of 2-[3-bromo-1-(3-chloro-2-pyridinyl)-1H-pyrazol-5-yl]-6-chloro-8-methyl-4H-3,1-benzoxazine-4-one. In addition, the filtrate was concentrated under reduced pressure, and the resulting residue was subjected to silica gel column chromatography to obtain 0.093 g of 2-[3-bromo-1-(3-chloro-2-pyridinyl)-1H-pyrazol-5-yl]-6-chloro-8-methyl-4H-3,1-benzoxazine-4-one of the formula:

Quelle