Reaction #487547

Reaction equation

(2S,4R)-1-tert-butyl 2-methyl 4-hydroxypyrrolidine-1,2-dicarboxylate

carbonyl diimidazole

4-bromoisoindole

→

solid

Yield 79.4%

(2S,4R)-1-tert-butyl 2-methyl 4-(4-bromoisoindoline-2-carbonyloxy)pyrrolidine-1,2-dicarboxylate

Yield 79.4%

Solvents

N,N-dimethylacetamide

Conditions

Workup

1. 1
   TemperatureAfter cooling down
2. 2
   Extractionthe reaction mixture was extracted with 50 mL of EtOAc
3. 3
   Washwashed with water, brine
4. 4
   Dryingdried over Na2SO4
5. 5
   FiltrationAfter filtration and concentration
6. 6
   Otherthe residue was purified by flash column chromatography on silica gel

Procedure

To a solution containing 0.5 g of (2S,4R)-1-tert-butyl 2-methyl 4-hydroxypyrrolidine-1,2-dicarboxylate (2 mmol) in 5 mL of N,N-dimethylacetamide, was added 370 mg of carbonyl diimidazole (1.1 equiv.). The reaction was heated at 60° C. for 1 hr, then 400 mg of 4-bromoisoindole (2 mmol) was added. The reaction was continued at 60° C. overnight. After cooling down, the reaction mixture was extracted with 50 mL of EtOAc, and washed with water, brine, and dried over Na2SO4. After filtration and concentration, the residue was purified by flash column chromatography on silica gel using heptanes/EtOAc (v/v 5/2), giving white solid 745 mg (79%). LC-MS: m/z=369.2 (ES+, M+1-Boc).

Source