Water → 3,4-dihydro-1,10-dimethyl-1H-1,4-oxazino[4,3-a]indole-1-acetic acid ethyl ester

HRID 596955Notes

Reaction equation

HRID 596955 reaction equation
[CH3:1][C:2]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[N:4]([CH2:11][CH2:12][OH:13])[CH:3]=1.[C:14]([O:20][CH2:21][CH3:22])(=[O:19])[CH2:15][C:16]([CH3:18])=O.C1(C)C=CC(S(O)(=O)=O)=CC=1.O>C1(C)C=CC=CC=1>[CH2:21]([O:20][C:14](=[O:19])[CH2:15][C:16]1([CH3:18])[C:3]2=[C:2]([CH3:1])[C:10]3[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=3[N:4]2[CH2:11][CH2:12][O:13]1)[CH3:22]

Participants

6

Reactant 4

HCID 962WaterHCID 6101p-Toluenesulfonic acidHCID 8868Ethyl AcetoacetateHCID 122267423-Methylindole-1-ethanol

Product 1

HCID 544519033,4-dihydro-1,10-dimethyl-1H-1,4-oxazino[4,3-a]indole-1-acetic acid ethyl ester

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

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.

Workup

  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

Sources & evidence

ORD record
ord-b84ffc008e81427eb950fbcb6461d5c4
Source dataset
uspto-grants-1977_03
Patent number
US04012511

Reaction notes

Loading…