反应详情

2.5 g of N-[2-(4-amino-3-methoxyphenyl)ethyl]trifluoroacetamide and 1.9 ml of mesoxalic acid diethyl ester are dissolved in 25 ml of acetic acid and refluxed for 4 hours. The mixture is concentrated, the residue dissolved in ethyl acetate and extracted twice by shaking with saturated sodium bicarbonate solution. The mixture is concentrated and chromatographed on silica gel with cyclohexane/ethyl acetate 1:1, thus obtaining 2.5 g of 2,3-dihydro-3-hydroxy-7-methoxy-2-oxo-5-(trifluoroacetamidoethyl)-3-indolecarboxylic acid ethyl ester, mp 115°-117° C.

1. temperaturerefluxed for 4 hours
2. concentrationThe mixture is concentrated
3. dissolutionthe residue dissolved in ethyl acetate
4. extractionextracted twice
5. concentrationThe mixture is concentrated
6. customchromatographed on silica gel with cyclohexane/ethyl acetate 1:1