Reaktion #487547

Reaktionsgleichung

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

carbonyl diimidazole

4-bromoisoindole

→

solid

Ausbeute 79.4%

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

Ausbeute 79.4%

Lösungsmittel

N,N-dimethylacetamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturAfter cooling down
2. 2
   Extraktionthe reaction mixture was extracted with 50 mL of EtOAc
3. 3
   Waschenwashed with water, brine
4. 4
   Trocknendried over Na2SO4
5. 5
   FiltrationAfter filtration and concentration
6. 6
   Sonstigethe residue was purified by flash column chromatography on silica gel

Vorschrift

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).

Quelle