反应详情

A mixture of the intermediate of formula III, 3-methylindole-1-ethanol (26.5 g., 0.15 mole), described in Example 1, in toluene (600 ml.), ethyl acetoacetate (36 g., 0.20 mole) and p-toluenesulfonic acid (2.0 g.) is heated at reflux for 6 hr. using a water separator. The toluene solution is washed with water, 5% bicarbonate solution, and again with water. The solution is then dried over sodium sulfate and the solvent evaporated under reduced pressure to give an oil. The oil was subjected to chromatograhy on silica gel. Elution with 10% ethyl acetate is benzene and concentration of the eluate affords the ester, 3,4-dihydro-1,10-dimethyl-1H-1,4-oxazino[4,3-a]indole-1-acetic acid ethyl ester, as an oil, γmaxfilm 1725 cm-1.

1. temperatureat reflux for 6 hr
2. washThe toluene solution is washed with water, 5% bicarbonate solution
3. dry with materialThe solution is then dried over sodium sulfate
4. customthe solvent evaporated under reduced pressure
5. customto give an oil
6. washElution with 10% ethyl acetate