Reaktion #89789

Reaktionsgleichung

4-hydrazinobenzoic acid

isopropylmethylketone

→

desired product

Ausbeute 80.1%

2,3,3-Trimethyl-5-carboxy-3H-indole

Ausbeute 80.1%

Lösungsmittel

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturunder reflux in an oil bath for 20 h
2. 2
   Sonstigewas evaporated off under reduced pressure and to it
3. 3
   workup.ADDITIONwas added a saturated aqueous solution of NaHCO3 (50 mL)
4. 4
   Waschenwashed with CH2Cl2 (3×40 mL)
5. 5
   Extraktionextracted with CH2Cl2 (3×50 mL)
6. 6
   TrocknenThe combined organic solution was then dried with Na2SO4
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated to dryness under reduced pressure

Vorschrift

A solution of 4-hydrazinobenzoic acid (10.0 g, 65.7 mmol), isopropylmethylketone (21.1 mL, 197 mmol) in acetic acid (35 mL) was heated under reflux in an oil bath for 20 h. After cooling to ambient temperature the solvent was evaporated off under reduced pressure and to it was added a saturated aqueous solution of NaHCO3 (50 mL) and washed with CH2Cl2 (3×40 mL). The pH of the aqueous solution was adjusted with 1 M aqueous HCl to ca. 2, and then extracted with CH2Cl2 (3×50 mL). The combined organic solution was then dried with Na2SO4, filtered and concentrated to dryness under reduced pressure to yield the desired product (10.7 g, 80%) as a brownish solid.

Quelle