Ethyl ketone → HCID 13338606, compound

HRID 2417920Notes

Reaction equation

HRID 2417920 reaction equation
[N:1]1[CH2:2][CH2:3][CH2:4][N:5]2[C:9]3[CH:10]=[C:11]([NH2:14])[CH:12]=[CH:13][C:8]=3[S:7][C:6]=12.[CH3:15][CH2:16][C:17](=O)[CH2:18][CH3:19].[BH4-].[Na+].[OH-].[NH4+]>C(O)(=O)C>[CH2:16]([CH:17]([NH:14][C:11]1[CH:12]=[CH:13][C:8]2[S:7][C:6]3=[N:1][CH2:2][CH2:3][CH2:4][N:5]3[C:9]=2[CH:10]=1)[CH2:18][CH3:19])[CH3:15]

Participants

6

Reactant 4

HCID 7288Ethyl ketoneHCID 14923Ammonium HydroxideHCID 4311764Sodium borohydrideHCID 133385843,4-Dihydro-2H-pyrimido[2,1-b][1,3]benzothiazol-7-amine

Product 1

HCID 13338606HCID 13338606, compound

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

A mixture of 3 parts of 3,4-dihydro-2H-pyrimido[2,1-b]benzothiazol-7-amine, 1.6 parts of 3-pentanone and 30 parts of acetic acid is stirred for 10 minutes at room temperature. Then there is added portionwise 1 part of sodium borohydride at a temperature between 18°-20° C. (cooling is necessary). Upon completion, stirring is continued for 20 minutes at room temperature. The reaction mixture is alkalized to pH 8-9 with ammonium hydroxide while cooling. The product is extracted with trichloromethane. The aqueous phase is separated and extracted with trichloromethane. The combined organic phases are 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 2,2'-oxybispropane. The product is filtered off and dried, yielding 2.2 parts of N-(1-ethylpropyl)-3,4-dihydro-2H-pyrimido[2,1-b]benzothiazol-7-amine; mp. 114.4° C.

Workup

  1. temperature(cooling is necessary)
  2. stirringUpon completion, stirring
  3. waitis continued for 20 minutes at room temperature
  4. temperaturewhile cooling
  5. extractionThe product is extracted with trichloromethane
  6. customThe aqueous phase is separated
  7. extractionextracted with trichloromethane
  8. washThe combined organic phases are washed with water
  9. customdried
  10. filtrationfiltered
  11. customevaporated
  12. customThe residue is purified by column-chromatography over silica gel using
  13. additiona mixture of trichloromethane and methanol (95:5 by volume)
  14. customThe pure fractions are collected
  15. customthe eluent is evaporated
  16. customThe residue is crystallized from 2,2'-oxybispropane
  17. filtrationThe product is filtered off
  18. customdried

Sources & evidence

ORD record
ord-3dbd72c2b4bc48e19f43b499579061d5
Source dataset
uspto-grants-1984_09
Patent number
US04471117

Reaction notes

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