반응 #11904

반응 방정식

(R)-4-carbobenzyloxypiperazine-2-carboxylic acid

1,2-dichloro-fluoro-5-nitrobenzene

water

dimethylformamide

→

title compound

수율 94.2%

(R)-4-Carbobenzyloxy-1-(4,5-Dichloro-2-Nitrophenyl)-Piperazine-2-Carboxylic Acid

수율 94.2%

용매

triethylamine

반응 조건

후처리

1. 1
   기타at ambient temperature
2. 2
   기타overnight
3. 3
   농축The dark orange solution is concentrated under reduced pressure (1–2 mm, <50° C.) to an orange oily residue
4. 4
   workup.DISSOLUTIONThis oil is dissolved in 400 mL of ethyl acetate
5. 5
   세척washed with 100 mL of 1 N HCl (2×), with 150 mL of water (2×), and 100 mL of brine
6. 6
   건조The organic layer is dried over MgSO4
7. 7
   여과filtered
8. 8
   농축concentrated

실험 절차

To a slurry containing 5.0 g of (R)-4-carbobenzyloxypiperazine-2-carboxylic acid, 4.2 g of 1,2-dichloro-fluoro-5-nitrobenzene, 85 mL of water and 170 mL of dimethylformamide is added slowly 5.3 mL of triethylamine. The solution is heated to 50° C. for 5 hours, then at ambient temperature overnight. The dark orange solution is concentrated under reduced pressure (1–2 mm, <50° C.) to an orange oily residue. This oil is dissolved in 400 mL of ethyl acetate and washed with 100 mL of 1 N HCl (2×), with 150 mL of water (2×), and 100 mL of brine. The organic layer is dried over MgSO4, filtered and concentrated to give 8.1 g (94.2%) of title compound as an orange solid foam.

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