Methyl iodide → 4-hydroxy-2-methyl-N-(2-thiazolyl)-2H-thieno[2,3-e]-1,2-thiazine-3-carboxamide1,1-dioxide

HRID 2163470Notes

Reaction equation

HRID 2163470 reaction equation
[OH:1][C:2]1[C:7]2[S:8][CH:9]=[CH:10][C:6]=2[S:5](=[O:12])(=[O:11])[NH:4][C:3]=1[C:13]([NH:15][C:16]1[S:17][CH:18]=[CH:19][N:20]=1)=[O:14].[H-].[Na+].[CH3:23]I.[Na]>CN(C)C=O>[OH:1][C:2]1[C:7]2[S:8][CH:9]=[CH:10][C:6]=2[S:5](=[O:12])(=[O:11])[N:4]([CH3:23])[C:3]=1[C:13]([NH:15][C:16]1[S:17][CH:18]=[CH:19][N:20]=1)=[O:14]

Participants

6

Reactant 4

HCID 6328Methyl iodideHCID 24758Sodium hydrideHCID 5360545SodiumHCID 546941064-hydroxy-N-(2-thiazolyl)-2H-thieno[2,3-e]-1,2-thiazine-3-carboxamide 1,1-dioxide

Product 1

HCID 547213384-hydroxy-2-methyl-N-(2-thiazolyl)-2H-thieno[2,3-e]-1,2-thiazine-3-carboxamide1,1-dioxide

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent2×

Procedure

0.329 g (1 mmol) of 4-hydroxy-N-(2-thiazolyl)-2H-thieno[2,3-e]-1,2-thiazine-3-carboxamide 1,1-dioxide are dissolved in 2 ml. of absolute dimethylformamide and added at 0° C. to a stirred suspension of 0.026 g (1.1 mmol) of sodium hydride in 1 ml. of absolute dimethylformamide. The mixture is stirred at room temperature for a further 1 hour. 0.1 ml. (0.226 g; 1.6 mmol) of methyl iodide are then added to the sodium salt solution and allowed to react for a further 1 hour. After distillation of the solvent, the residue is taken up in 200 ml of methylene chloride and 10 ml. of 0.5-N hydrochloric acid. The organic phase is separated and shaken out with a total of 50 ml. of a 0.5% sodium bicarbonate solution. The aqueous layer, which now contains the desired product, is back-extracted several times with methylene chloride and acidified with hydrochloric acid. The acidic aqueous phase is extracted with methylene chloride and the combined organic extracts dried over sodium sulphate and evaporated. The crystalline residue is digested with a small amount of cold ethanol for purification. There is obtained 4-hydroxy-2-methyl-N-(2-thiazolyl)-2H-thieno[2,3-e]-1,2-thiazine-3-carboxamide 1,1-dioxide of melting point 217° C. (decomposition).

Workup

  1. customto react for a further 1 hour
  2. distillationAfter distillation of the solvent
  3. customThe organic phase is separated
  4. stirringshaken out with a total of 50 ml
  5. extractionis back-extracted several times with methylene chloride
  6. extractionThe acidic aqueous phase is extracted with methylene chloride
  7. dry with materialthe combined organic extracts dried over sodium sulphate
  8. customevaporated
  9. customThe crystalline residue is digested with a small amount of cold ethanol for purification

Sources & evidence

ORD record
ord-df901407b5674a1d8c3011cf495da5a3
Source dataset
uspto-grants-1979_01
Patent number
US04134898

Reaction notes

Loading…