Hydrochloric Acid → 6-Bromo-2-(3-carboxypropyl)phthalazin-1(2H)-one

HRID 622129Notes

Reaction equation

HRID 622129 reaction equation
[Br:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[C:8](=[O:12])[NH:7][N:6]=[CH:5]2.[OH-].[K+].Br[CH2:16][CH2:17][CH2:18][C:19]([O:21]CC)=[O:20].Cl>CS(C)=O.O.C(O)C>[Br:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[C:8](=[O:12])[N:7]([CH2:16][CH2:17][CH2:18][C:19]([OH:21])=[O:20])[N:6]=[CH:5]2

Participants

8

Reactant 4

HCID 313Hydrochloric AcidHCID 14797Potassium HydroxideHCID 76300Ethyl 4-bromobutyrateHCID 115359186-Bromophthalazin-1(2h)-one

Product 1

HCID 142348436-Bromo-2-(3-carboxypropyl)phthalazin-1(2H)-one

Reagents, catalysts & solvents 3

HCID 679Dimethyl SulfoxideSolventHCID 702EthanolSolventHCID 962WaterSolvent

Conditions

Temperature
25 °C

Procedure

To a slurry of 56 gm 6-bromophthalazin-1(2H)-one (0.25 mole) in 600 ml DMSO was added 110 ml 45% KOH followed by 58.5 gm ethyl 4-bromobutyrate. The temperature of the mildly exothermic reaction was moderated with a water bath (ca. 25° C.) and was stirred for 20 hours. Ethanol (750 ml) was added, then the mixture was acidified with 125 ml concentrated HCl, diluted with 2500 ml water over about 30 minutes, stirred an additional 30 minutes, filtered, washed with water and isopropanol and dried. The product weighed 63.6 gm. A tlc of the product showed product, Rf =0.43 plus a trace of starting material, Rf =0.63.

Workup

  1. customThe temperature of the mildly exothermic reaction
  2. customwas moderated with a water bath
  3. stirringstirred an additional 30 minutes
  4. filtrationfiltered
  5. washwashed with water and isopropanol
  6. customdried

Sources & evidence

ORD record
ord-035840a695314214ba940aa06c69ebe0
Source dataset
uspto-grants-1988_09
Patent number
US04769369

Reaction notes

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