反应详情

A magnetically stirred solution of 5 grams of 5-iodoisatoic anhydride (0.0173 mol), 5.85 grams of β-alanine benzyl ester tosylate (0.0173 mol), 35 mL pyridine, and 0.5 of dimethylaminopyridine (0.0041 mol) was heated to 80° C. for 2 hrs. The reaction mixture was allowed to cool to room temperature and concentrated in vacuo. The resulting residue was dissolved in 100mL ethyl acetate and washed 2×50 mL of 10% cupric sulfate, 1×50 mL sat. sodium bicarbonate, 1×50 mL brine, dried over sodium sulfate, filtered and concentrated in vacuo. The product was further purified by column chromatography, using silica gel, eluting with a 1:1 mixture of ethyl acetate and hexane (TLC, SIO2, 1:1 EtOAc/hexane, Rf =0.65, υν positive) to yield 1.85 grams (25%) of N-(2-amino-5-iodobenzoyl)-β-alanine benzyl ester. 1H NMR (CDCl3, δTMS) 7.54 (1H, d, 4JHH =2 Hz, Ar--H o--CON), 7.42 (1H, dd, 3JHH =9 Hz, 4JHH =2 Hz, Ar--H p--CON), 7.38-7.32 (5H, s, ArH Ph), 6.65 (1H, bt, 3JHH =6 Hz, CONH), 6.46 (1H, d, 3JHH =9 Hz, Ar--H m--CON), 5.16 (2H, s, OCH2), 3.68 (2H, q, 3JHH =6 Hz, NCH2), 2.69 (2H, t, 3JHH =6 Hz, CH2CO2). 13C NMR (CDCl3,δTMS) 172.4, 167.8, 148.2, 140.6, 135.6, 135.5, 128.7, 128.4, 128.3, 119.3, 118.1, 76.3, 66.7, 35.2, 34.0.

1. concentrationconcentrated in vacuo
2. dissolutionThe resulting residue was dissolved in 100mL ethyl acetate
3. washwashed 2×50 mL of 10% cupric sulfate, 1×50 mL sat. sodium bicarbonate, 1×50 mL brine
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe product was further purified by column chromatography
8. washeluting with a 1:1 mixture of ethyl acetate and hexane (TLC, SIO2, 1:1 EtOAc/hexane, Rf =0.65, υν positive)