Tetrahydrofuran → HCID 19037056, compound

HRID 264834Notes

Reaction equation

HRID 264834 reaction equation
[OH:1][C:2]1[C:3]([CH2:22][O:23][CH3:24])([CH2:19][O:20][CH3:21])[O:4][C:5]2[CH:15]=[CH:14][C:13]([N+:16]([O-:18])=[O:17])=[CH:12][C:6]=2[C:7]=1[C:8](=[S:11])[NH:9][CH3:10].O1CCCC1.[BH4-].[Na+]>CO>[OH:1][CH:2]1[CH:7]([C:8](=[S:11])[NH:9][CH3:10])[C:6]2[CH:12]=[C:13]([N+:16]([O-:18])=[O:17])[CH:14]=[CH:15][C:5]=2[O:4][C:3]1([CH2:22][O:23][CH3:24])[CH2:19][O:20][CH3:21]

Participants

5

Reactant 3

HCID 8028TetrahydrofuranHCID 4311764Sodium borohydrideHCID 136381156HCID 136381156, compound

Product 1

HCID 19037056HCID 19037056, compoundYield 36.8%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To a mixture of 2.7 g of 3-hydroxy-2,2-bis(methoxymethyl)-N-methyl-6-nitro-2H-1-benzopyran-4-carbothioamide, 12 ml of tetrahydrofuran and 46 ml of methanol was added 1.1 g of sodium borohydride (NaBH4) with stirring under ice-cooling and stirred under ice-cooling for 2 hours and subsequently further stirred at room temperature for 24 hours. The reaction solution was vacuum-distilled, water was added therein and the resultant mixture was extracted with methylene chloride. An organic layer was washed with water and dried. The solvent was distilled to obtain 1.0 g of 3,4-dihydro-3-hydroxy-2,2-bis(methoxymethyl)-N-methyl-6-nitro-2H-1-benzopyran-4-carbothioamide. Subsequently, to 700 mg of the obtained benzopyran derivative were added 0.75 g of p-toluenesulfonyl chloride and 11 ml of pyridine. The resultant mixture was refluxed with heating for 30 minutes and the solvent was distilled. Ice water was added to the residue and it was acidified to be hydrochloric acid and extracted with methylene chloride. An organic layer was washed with water and dried and the solvent was distilled. The resultant residue was purified according to silica gel column chromatography (developing solution, MeOH:CH2Cl2 =5:95) to obtain 500 mg of 2,2-bis(methoxymethyl)-N-methyl-6-nitro-2H-1-benzopyran-4-carboxamide with a melting point of 147°-149° C.

Workup

  1. temperaturecooling
  2. stirringstirred under ice-
  3. temperaturecooling for 2 hours
  4. stirringsubsequently further stirred at room temperature for 24 hours
  5. distillationThe reaction solution was vacuum-distilled
  6. additionwater was added
  7. extractionthe resultant mixture was extracted with methylene chloride
  8. washAn organic layer was washed with water
  9. customdried
  10. distillationThe solvent was distilled

Sources & evidence

ORD record
ord-981121a74a0f4755a0a4ad420602eb31
Source dataset
uspto-grants-1997_07
Patent number
US05646308

Reaction notes

Loading…