Acetamide → N-(5-nitro-pyrazin-2-yl)-methanesulfonamide

HRID 719871Notes

Reaction equation

HRID 719871 reaction equation
C(N)(=O)C.Br[C:6]1[CH:11]=[N:10][C:9]([N+:12]([O-:14])=[O:13])=[CH:8][N:7]=1.[CH3:15][S:16]([NH2:19])(=[O:18])=[O:17].C(=O)([O-])[O-].[K+].[K+].Cl.C>O>[N+:12]([C:9]1[N:10]=[CH:11][C:6]([NH:19][S:16]([CH3:15])(=[O:18])=[O:17])=[N:7][CH:8]=1)([O-:14])=[O:13]

Participants

8

Reactant 6

HCID 178AcetamideHCID 297MethaneHCID 313Hydrochloric AcidHCID 11430Potassium CarbonateHCID 72879MethanesulfonamideHCID 140869592-Bromo-5-nitropyrazine

Product 1

HCID 21897390N-(5-nitro-pyrazin-2-yl)-methanesulfonamideYield 40.7%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
145 °C

Procedure

A solution of molten acetamide (1.58 g, 26.7 mmol) heated to 90° C. was treated with a mixture of 2-bromo-5-nitropyrazine (1.34 g, 6.58 mmol), methanesulfonamide (1.88 g, 19.7 mmol), and potassium carbonate (2.30 g, 16.6 mmol). The resulting mixture was quickly brought to 145° C. The resulting solution was stirred at 145° C. for 30 min. At this time, the reaction was cooled to 25° C. and then was treated with water (4 mL). This solution was cooled to 0° C. and then was treated with a 1N aqueous hydrochloric acid solution until the pH of the solution was adjusted to pH=8. This solution was treated with charcoal and was filtered through a pad of celite (9/1 methylene chloride/methanol wash). The filtrate was partitioned, and the aqueous layer was extracted with a solution of 9/1 methylene chloride/methanol. The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230–400 mesh, ethyl acetate) afforded N-(5-nitro-pyrazin-2-yl)-methanesulfonamide (583.9 mg, 40.6%) as a yellow solid: mp 204–207° C.; EI-HRMS m/e calcd for C5H6N4O4S (M+H)+ 219.0183, found 219.0185.

Workup

  1. customwas quickly brought to 145° C
  2. temperatureAt this time, the reaction was cooled to 25° C.
  3. temperatureThis solution was cooled to 0° C.
  4. filtrationwas filtered through a pad of celite (9/1 methylene chloride/methanol wash)
  5. customThe filtrate was partitioned
  6. extractionthe aqueous layer was extracted with a solution of 9/1 methylene chloride/methanol
  7. dry with materialThe combined organic layers were dried over sodium sulfate
  8. filtrationfiltered
  9. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-9ac044b2a2b74b85a46c25fc068d0ffe
Source dataset
uspto-grants-2006_11
Patent number
US07132425B2

Reaction notes

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