反应详情

To a ice cooled solution of acetic acid 2-acetoxy-1-(3,5-bis-chlorocarbonyl-2,4,6-triiodo-phenylcarbamoyl)-ethyl ester (20 g, 0.026 mol) in anhydrous DMAC (20 ml) were added dropwise a solution of 2-[(2,2-Dimethyl-[1,3]dioxolan-4-yl-methyl)-amino]-ethanol (4.6 g, 0.026 mol) in DMAC (20 mL) followed by triethylamine (˜3 g). The mixture was stirred at room temperature for 24 h and then poured over icewater (0.75 litre). A white precipitate formed. This was collected and washed with cold water. The filter cake was then dissolved in ethyl acetate and washed with brine. The organics were collected, dried over MgSO4, filtered and evaporated to dryness. The product was purified by silica column chromatography eluting with Petroleum ether/ethyl acetate. Two peaks closely eluting at 80% ethyl acetate were analysed by NMR and mass spec, and show to both contain the desired material. These were combined post analysis to give the desired product (10 mmol, Yield=38%). The structure was confirmed by Mass Spec (ESI) m/z: Calculated for C23H26Cl I3N2O10 [M+H]+906.64. Found 906.93. 1H NMR (CDCl3; 300 MHz) δ=1.33 (2s, 3H) 1.45 (2s, 3H) 2.02 (s, 3H) 2.26 (s, 3H) 3-3.5 (m, 4H) 3.5-3.9 (m, 3H) 3.9-4.3 (m, 2H) 4.5 (m, 1H) 4.6-4.8 (m, 2H) 5.62 (NH singlet, 1H)

1. additionpoured over icewater (0.75 litre)
2. customA white precipitate formed
3. customThis was collected
4. washwashed with cold water
5. dissolutionThe filter cake was then dissolved in ethyl acetate
6. washwashed with brine
7. customThe organics were collected
8. dry with materialdried over MgSO4
9. filtrationfiltered
10. customevaporated to dryness
11. customThe product was purified by silica column chromatography
12. washeluting with Petroleum ether/ethyl acetate
13. washTwo peaks closely eluting at 80% ethyl acetate