Acetic Acid → HCID 12873977, compound

HRID 1902635Notes

Reaction equation

HRID 1902635 reaction equation
[N:1]1[CH:2]=[CH:3][N:4]2[C:8]3[CH:9]=[C:10]([NH2:13])[CH:11]=[CH:12][C:7]=3[S:6][C:5]=12.C(O)(=O)C.[BH4-].[Na+].[OH-].[NH4+].[CH3:22][C:23](=O)[CH3:24]>>[CH3:22][CH:23]([NH:13][C:10]1[CH:11]=[CH:12][C:7]2[S:6][C:5]3=[N:1][CH2:2][CH2:3][N:4]3[C:8]=2[CH:9]=1)[CH3:24]

Participants

6

Reactant 5

HCID 176Acetic AcidHCID 180AcetoneHCID 14923Ammonium HydroxideHCID 4311764Sodium borohydrideHCID 20514572HCID 20514572, compound

Product 1

HCID 12873977HCID 12873977, compoundYield 54%

Procedure

To a stirred mixture of 4 parts of imidazo[2,1-b]-benzothiazol-6-amine and 30 parts of acetic acid are added 1.6 parts of 2-propanone. After stirring for 10 minutes at room temperature, 0.6 parts of sodium borohydride are added portionwise at 20° C. (cooling is necessary). Upon completion, stirring is continued for 10 minutes. The reaction mixture is poured onto water and the whole is alkalized to pH 7-8 with ammonium hydroxide. The product is extracted with trichloromethane. The extract is washed with water, dried, filtered and evaporated. The residue is purified by column-chromatography over silica gel using a mixture of trichloromethane and methanol (95:5 by volume), saturated with ammonia, as eluent. The pure fractions are collected and the eluent is evaporated. The residue is crystallized from 4-methyl-2-pentanone. The product is filtered off and dried, yielding 2.5 parts (54%) of 2,3-dihydro-N-(1-methylethyl)imidazo[2,1-b]benzothiazol-6-amine; mp. 128.2° C.

Workup

  1. temperature(cooling is necessary)
  2. stirringUpon completion, stirring
  3. waitis continued for 10 minutes
  4. additionThe reaction mixture is poured onto water
  5. extractionThe product is extracted with trichloromethane
  6. washThe extract is washed with water
  7. customdried
  8. filtrationfiltered
  9. customevaporated
  10. customThe residue is purified by column-chromatography over silica gel using
  11. additiona mixture of trichloromethane and methanol (95:5 by volume)
  12. customThe pure fractions are collected
  13. customthe eluent is evaporated
  14. customThe residue is crystallized from 4-methyl-2-pentanone
  15. filtrationThe product is filtered off
  16. customdried

Sources & evidence

ORD record
ord-977a071428ca46d7b53220d76d4c44ca
Source dataset
uspto-grants-1982_12
Patent number
US04364942

Reaction notes

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