Cyclopropylamine → 7-Hydroxyindole

HRID 439395Notes

Reaction equation

HRID 439395 reaction equation
[NH:1]1[C:9]2[C:4](=[CH:5]C=CC=2)[C:3](=[O:10])[CH2:2]1.[CH:11]1(N)[CH2:13][CH2:12]1>C1(C)C=CC=CC=1.[Ti](Cl)(Cl)(Cl)Cl>[NH:1]1[C:2]2[C:13](=[CH:12][CH:5]=[CH:4][C:3]=2[OH:10])[CH:11]=[CH:9]1

Participants

5

Reactant 2

HCID 69828CyclopropylamineHCID 2309153-Indolinone

Product 1

HCID 27376517-Hydroxyindole

Reagents, catalysts & solvents 2

HCID 24193Titanium TetrachlorideCatalystHCID 1140TolueneSolvent2×

Conditions

Temperature
-10 °C

Procedure

7-Chloroacetyloxy-1,4-dihydro-4-methylcyclopent b!indol-3(2H)-one (15.0 g) and cyclopropylamine (9.6 g) were dissolved in 300 ml toluene and cooled to -10° C. Titanium tetrachloride (6.3 g) dissolved in 50 ml toluene was added slowly to the first solution. The reaction mixture was allowed to come up to room temperature and stirred overnight. The next day another 1.5 equivalents of the amine (4.6 g) was added to the reaction mixture and the mixture was stirred for one hour. The reaction mixture was filtered through a pad of silica gel, eluting with 3:1 hexane/ethyl acetate, giving a yellow oil after removal of solvents. 3-Cyclopropylamino-4-methyl-1,2,3,4-tetrahydrocyclopent b!-indol-7-ol was isolated as a light yellow solid (3.3 g) after flash chromatography and recrystallization from ethyl acetate.

Workup

  1. additionwas added slowly to the first solution
  2. customto come up to room temperature
  3. stirringthe mixture was stirred for one hour
  4. filtrationThe reaction mixture was filtered through a pad of silica gel
  5. washeluting with 3:1 hexane/ethyl acetate
  6. customgiving a yellow oil
  7. customafter removal of solvents

Sources & evidence

ORD record
ord-752619c4d85e4a9cad4738d3192ff18b
Source dataset
uspto-grants-1996_05
Patent number
US05514700

Reaction notes

Loading…