Water → Phthalimide

HRID 648608Notes

Reaction equation

HRID 648608 reaction equation
S(C1C=CC(C)=CC=1)([O-])(=O)=O.[C:12]1(=[O:22])[NH:16][C:15](=[O:17])[C:14]2=[CH:18][CH:19]=[CH:20][CH:21]=[C:13]12.[K].O>CS(C)=O>[C:12]1(=[O:22])[NH:16][C:15](=[O:17])[C:14]2=[CH:18][CH:19]=[CH:20][CH:21]=[C:13]12

Participants

5

Reactant 3

HCID 962WaterHCID 85570p-Toluenesulfonate2×HCID 24194345Phthalimide potassium salt

Product 1

HCID 6809PhthalimideYield 39.9%

Reagents, catalysts & solvents 1

HCID 679Dimethyl SulfoxideSolvent

Procedure

The title B tosylate (19.2 mmol) and purified potassium phthalimide (6.4 g, 34.6 mmol, 1.8 equiv.) in dimethylsulfoxide (70 ml, Burdick & Jackson) are heated at 90°-100° C. for 21/2 hours (checked by TLC Et2O-pet ether 2:1, no tosylate remaining). After cooling to room temperature, water (90 ml) is added. The mixture is poured into ice water (~350 ml) and stirred 30 minutes. The straw colored solid is harvested by filtration and washed with more water. The solid is dissolved in warm ethyl acetate (150 ml), washed with water (3×50 ml), dried (MgSO4), filtered and freed of solvent in vacuo. The remaining solid is recrystallized from isopropyl ether (~150 ml) to give corresponding phthalimide (13.8 mmol) is dissolved in distilled CH2Cl2 (24 ml) and distilled ethanol (104 ml) in an argon atmosphere. Anhydrous hydrazine (0.78 ml, 25.6 mmol) is added. The mixture is stirred at room temperature. After 8 hours an additional 0.2 ml of hydrazine is added and the mixture is stirred an additional 15 hours at room temperature. A solid is removed by filtration and washed with more CH2Cl2. The filtrate is taken to dryness in vacuo (on the pump at end). Cold 0.5N HCl solution (80 ml) is added. The acidic solution is washed with ether (2×100 ml) and then basified with solid K2CO3. The amine is extracted into CHCl3 (3×100 ml), dried (MgSO4) and freed of solvent in vacuo leaving an oil. Ether (100 ml) is added to this oil. After cooling in an ice bath, the solid is removed by filtration. The solvent is removed from the filtrate in vacuo leaving title amine. The material is used without further purification.

Workup

  1. temperatureare heated at 90°-100° C. for 21/2 hours (
  2. filtrationThe straw colored solid is harvested by filtration
  3. washwashed with more water
  4. dissolutionThe solid is dissolved in warm ethyl acetate (150 ml)
  5. washwashed with water (3×50 ml)
  6. dry with materialdried (MgSO4)
  7. filtrationfiltered
  8. customThe remaining solid is recrystallized from isopropyl ether (~150 ml)

Sources & evidence

ORD record
ord-192df9903e2346b2b59f670a9c4e7b88
Source dataset
uspto-grants-1988_04
Patent number
US04735962

Reaction notes

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