Hydrochloric Acid → HCID 18442774, compound

HRID 546428Notes

Reaction equation

HRID 546428 reaction equation
[Cl:1][C:2]1[S:3][C:4]2[CH2:10][CH2:9][C:8](=O)[CH2:7][C:5]=2[N:6]=1.C([O-])(=O)C.[NH4+].[C:17]([BH3-])#[N:18].[Na+].Cl.[CH2:22]=O>CO>[Cl:1][C:2]1[S:3][C:4]2[CH2:10][CH2:9][CH:8]([N:18]([CH3:17])[CH3:22])[CH2:7][C:5]=2[N:6]=1

Participants

7

Reactant 5

HCID 313Hydrochloric AcidHCID 712FormaldehydeHCID 517165Ammonium AcetateHCID 5003444Sodium cyanoborohydride3×HCID 17842476HCID 17842476, compound

Product 1

HCID 18442774HCID 18442774, compoundYield 32%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent2×

Procedure

2-Chloro-5-oxo-4,5,6,7-tetrahydrobenzo[d]thiazole (Helv. Cim. Acta., 1994, Vol. 77, p. 1256) (2.0 g) was dissolved in methanol (100 ml), and ammonium acetate (8.2 g) and sodium cyanoborohydride (4.0 g) were added to heat the mixture under reflux. After 20 hours, the reaction was stopped, hydrochloric acid was added to decompose excessive sodium cyanoborohydride before the solvent was distilled off under reduced pressure. The residue was alkalified with a 1N solution of sodium hydroxide and then extracted with dichloromethane. The resultant organic layer was dried over anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure to obtain a pale yellow oil. This oil was dissolved in methanol (50 ml), and an aqueous solution (4.29 g) of formaldehyde and sodium cyanoborohydride (3.49 g) were added to stir the mixture at room temperature for 12 hours. The solvent was distilled off under reduced pressure, and methylene chloride was added to the residue, the organic layer was washed with a saturated aqueous solution of sodium hydrogencarbonate and dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by column chromatography on silica gel (dichloromethane:methanol=10:1) to obtain the title compound (740 mg) as a pale yellow oil.

Workup

  1. temperatureto heat the mixture
  2. temperatureunder reflux
  3. distillationwas distilled off under reduced pressure
  4. extractionextracted with dichloromethane
  5. dry with materialThe resultant organic layer was dried over anhydrous magnesium sulfate
  6. distillationthe solvent was distilled off under reduced pressure
  7. customto obtain a pale yellow oil
  8. distillationThe solvent was distilled off under reduced pressure, and methylene chloride
  9. additionwas added to the residue
  10. washthe organic layer was washed with a saturated aqueous solution of sodium hydrogencarbonate
  11. dry with materialdried over anhydrous magnesium sulfate
  12. distillationThe solvent was distilled off under reduced pressure
  13. customthe residue was purified by column chromatography on silica gel (dichloromethane:methanol=10:1)

Sources & evidence

ORD record
ord-af7f194155cb424e956b5e192bef6046
Source dataset
uspto-grants-2011_05
Patent number
US07935824B2

Reaction notes

Loading…