Reaction #320246

Reaction equation

N,N'-Bis-[2,3-diacetyloxypropyl]-5-[3-bromo-2-oxo-1-pyrrolidinyl]-2,4,6-triiodo-1,3-benzenedicarboxamide

→

N,N'-bis-[2,3-diacetyloxypropyl]-5-[3-acetyloxy-2-oxo-1-pyrrolidinyl]-2,4,6-triiodo-1,3-benzenedicarboxamide

Yield 141.4%

Solvents

acetic acid

Conditions

Workup

1. 1
   Temperatureat reflux under nitrogen for 26 hours
2. 2
   Filtrationthe solids filtered off
3. 3
   OtherThe solvent was evaporated in vacuo
4. 4
   Otherthe residue was partitioned between ethyl acetate and brine
5. 5
   OtherThe organic layer was dried
6. 6
   Otherremoval of the solvent
7. 7
   Otherafforded the crude product as a colored foam
8. 8
   OtherPurification by silica gel flash chromatography

Procedure

N,N'-Bis-[2,3-diacetyloxypropyl]-5-[3-bromo-2-oxo-1-pyrrolidinyl]-2,4,6-triiodo-1,3-benzenedicarboxamide of example 5a, (6.43 g, 6.30 mmol) was dissolved in glacial acetic acid (63 ml) and then treated with silver acetate (4.21 g, 25.21 mmol) at reflux under nitrogen for 26 hours. The reaction mixture was cooled to room temperature and the solids filtered off. The solvent was evaporated in vacuo and the residue was partitioned between ethyl acetate and brine. The organic layer was dried and removal of the solvent afforded the crude product as a colored foam. Purification by silica gel flash chromatography furnished N,N'-bis-[2,3-diacetyloxypropyl]-5-[3-acetyloxy-2-oxo-1-pyrrolidinyl]-2,4,6-triiodo-1,3-benzenedicarboxamide as an off-white foam (4.45 g, 71% yield).

Source