Reaktion #344503

Reaktionsgleichung

1-(2,3,5,6-tetrafluoro-4-trifluoromethylphenyl)-5-hydroxymethylcarbonylamino-4-nitropyrazole

triethylamine

Methylaminosulfonyl chloride

→

1-(2,3,5,6-tetrafluoro-4-trifluoro methylphenyl)-5-methylaminosulfonyloxymethylcarbonylamino-4-nitropyrazole

Ausbeute 11.8%

Lösungsmittel

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   FiltrationThe reaction mixture was filtered
2. 2
   Sonstigeto remove a salt that
3. 3
   Sonstigehad formed
4. 4
   ExtraktionThe filtrate was extracted in succession with water, dilute hydrochloric acid
5. 5
   TrocknenThe organic phase was dried over anhydrous magnesium sulfate
6. 6
   Filtrationfiltered
7. 7
   SonstigeThe filtrate was evaporated under reduced pressure
8. 8
   Sonstigeleaving a brown oil
9. 9
   SonstigeThis oil was purified by column chromatography on silica gel, which
10. 10
    Waschenwas eluted with ethyl acetate: n-heptane (1:1)
11. 11
    Sonstigeto yield an oil
12. 12
    SonstigeThis oil crystallized in methylene chloride

Vorschrift

A stirred solution of 0.48 gram (0.0012 mole) of 1-(2,3,5,6-tetrafluoro-4-trifluoromethylphenyl)-5-hydroxymethylcarbonylamino-4-nitropyrazole and 0.27 gram (0.0027 mole) of triethylamine in 28.5 mL of methylene chloride was cooled in an ice-water bath. Methylaminosulfonyl chloride (0.55 gram, 0.0043 mole) was added dropwise, and the mixture was allowed to warm to room temperature and stir for four hours. The reaction mixture was filtered to remove a salt that had formed. The filtrate was extracted in succession with water, dilute hydrochloric acid, a saturated, aqueous sodium bicarbonate solution, and water. The organic phase was dried over anhydrous magnesium sulfate and filtered. The filtrate was evaporated under reduced pressure, leaving a brown oil. This oil was purified by column chromatography on silica gel, which was eluted with ethyl acetate: n-heptane (1:1) to yield an oil. This oil crystallized in methylene chloride and n-heptane to yield 0.07 gram of 1-(2,3,5,6-tetrafluoro-4-trifluoro methylphenyl)-5-methylaminosulfonyloxymethylcarbonylamino-4-nitropyrazole as an ivory-colored solid (Compound 21 of Table 1). The nmr spectrum was consistent with the proposed structure.

Quelle