反応 #521247

反応方程式

compound 2A

(2S)-1-[[(4-nitro-1-naphthalenyl)amino]carbonyl]-2-pyrrolidinecarboxylic acid methyl ester

DBU

DBU

→

title compound

収率 19.9%

Tetrahydro-2-(4-nitro-1-naphthalenyl)-1H-pyrrolo[1,2-c]imidazole-1,3(2H)-dione

収率 19.9%

溶媒

toluene

反応条件

後処理

1. 1
   その他formed
2. 2
   温度the reaction heated at 90° C. overnight
3. 3
   温度After cooling to RT
4. 4
   ろ過the reaction mixture was filtered
5. 5
   workup.ADDITIONThe filtrate was diluted with EtOAc
6. 6
   洗浄washed with 1 N aqueous HCl, water, brine
7. 7
   乾燥dried over MgSO4
8. 8
   濃縮concentrated under reduced pressure
9. 9
   その他to give a crude product, which
10. 10
    その他was chromatographed (silica gel)
11. 11
    洗浄eluting with CH2Cl2, 0.2% to 0.4% MeOH in CH2Cl2

実験手順

A suspension of compound 2A (410 mg, 1.29 mmol) and DBU (0.2 mL, 1.33 mmol) in toluene (10 mL) was heated at 80° C. for 2 hours. HPLC check of the reaction showed little product formed. Additional DBU (0.1 mL) was added and the reaction heated at 90° C. overnight. After cooling to RT, the reaction mixture was filtered. The filtrate was diluted with EtOAc, washed with 1 N aqueous HCl, water, brine, dried over MgSO4 and concentrated under reduced pressure to give a crude product, which was chromatographed (silica gel) eluting with CH2Cl2, 0.2% to 0.4% MeOH in CH2Cl2 to give the title compound (racemate) (80 mg) as a brown solid. mp. 215-217° C. HPLC: 97.5% at 2.51 min (retention time) (YMC S5 ODS column 4.6×50 mm; 10-90% aqueous methanol over 4 minutes containing 0.2% phosphoric acid, 4 mL/min, monitoring at 220 nM), MS (ES): m/z 312 [M+1]+.

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