2-Bromo-1,1-dimethoxyethane → 2-[4,5-Bis-(p-methoxyphenyl)-thiazol-2-ylthio]-acetaldehyde-dimethylacetal

HRID 544660Notes

Reaction equation

HRID 544660 reaction equation
[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([C:9]2[CH:13]([C:14]3[CH:19]=[CH:18][C:17]([O:20][CH3:21])=[CH:16][CH:15]=3)[S:12][C:11](=[S:22])[N:10]=2)=[CH:5][CH:4]=1.[CH3:23][O:24][CH:25]([O:28][CH3:29])[CH2:26]Br>[OH-].[Na+]>[CH3:23][O:24][CH:25]([O:28][CH3:29])[CH2:26][S:22][C:11]1[S:12][C:13]([C:14]2[CH:19]=[CH:18][C:17]([O:20][CH3:21])=[CH:16][CH:15]=2)=[C:9]([C:6]2[CH:7]=[CH:8][C:3]([O:2][CH3:1])=[CH:4][CH:5]=2)[N:10]=1

Participants

4

Procedure

15.0 g of 4,5-bis-(p-methoxyphenyl)-thiazoline-2-thione are dissolved in 50 ml of 2 N sodium hydroxide solution, 15.4 g of bromoacetaldehyde-dimethylacetal (2,2-dimethoxy-1-bromoethane) are added under nitrogen and the mixture is heated to 80° while stirring. The mixture is stirred at 80° for 2.5 hours, cooled to room temperature, extracted by shaking with 100 ml of toluene, the organic layer is removed and the aqueous phase is subsequently shaken with 50 ml of toluene. The organic phases are combined, washed twice with 30 ml of 2 N sodium hydroxide solution each time and then with 30 ml of 2 N hydrochloric acid, dried over magnesium sulphate, concentrated by evaporation under reduced pressure and carefully dried. The crude product is crystallised from hexane/methanol (50 ml+5 ml). 2-[4,5-bis-(p-methoxyphenyl)-thiazol-2-ylthio]-acetaldehyde-dimethylacetal having a melting point of 60°-61° is obtained.

Workup

  1. temperaturethe mixture is heated to 80°
  2. stirringThe mixture is stirred at 80° for 2.5 hours
  3. extractionextracted
  4. stirringby shaking with 100 ml of toluene
  5. customthe organic layer is removed
  6. stirringthe aqueous phase is subsequently shaken with 50 ml of toluene
  7. washwashed twice with 30 ml of 2 N sodium hydroxide solution each time
  8. dry with materialwith 30 ml of 2 N hydrochloric acid, dried over magnesium sulphate
  9. concentrationconcentrated by evaporation under reduced pressure
  10. customcarefully dried
  11. customThe crude product is crystallised from hexane/methanol (50 ml+5 ml)

Sources & evidence

ORD record
ord-57911f573c6b4996b9fabf14f1c9cf06
Source dataset
uspto-grants-1984_05
Patent number
US04451471

Reaction notes

Loading…