4-Acetoxyindole [5585-96-6-A] C10H9NO2
Step 1: In a 300-ml Erlenmeyer flask, dissolve 7 g of potassium hydroxide in 100 ml of ethanol. Cool the solution to -10 °C in an ice/salt bath and, while stirring, add a solution of 10 g of 6-hydroxy-2-nitrobenzaldehyde and 3.6 ml of nitromethane in a small amount of ethanol within 20 minutes. After acidifying with cold concentrated hydrochloric acid and adding water, extract five times with 20 ml each of diethyl ether. After drying with anhydrous sodium sulfate and concentrating under vacuum using a rotary evaporator, obtain a residue in the form of a yellow oil. Heat this with 30 ml of acetic anhydride and 20 g of anhydrous sodium acetate for 15 minutes under reflux. After cooling, add water, causing about 13 g (80% of the theoretical yield) of 2-β-dinitro-6-acetoxystyrene to precipitate.
Step 2: From this intermediate, 5 g is heated with 20 g of iron powder, 40 ml of ethanol, and 40 ml of glacial acetic acid until strong hydrogen evolution occurs under reflux. Once hydrogen evolution starts, continue heating for another 10 minutes. After this time, filter and wash with warm ethanol. Dissolve the filter cake in a small amount of water, make basic with sodium carbonate solution, and extract three times with 30 ml of diethyl ether each. Combine the filtrate with the ether extracts, dry with anhydrous sodium sulfate, and concentrate under vacuum using a rotary evaporator. The residue is 1 g of 4-acetoxyindole. This corresponds to 30% of the theoretical yield.
Description: 4-Acetoxyindole forms a colorless, water-insoluble crystalline powder. The substance is of scientific interest in the production of certain psychoactive tryptamine derivatives, such as psilocybin.
Source: Beer et al., J. Chem. Soc.; 1948, 1605-1609 • D. Trachsel and N. Richard - Psychedelic Chemistry, Nachtschatten, Solothurn CH, 2000
Delivered by: Mephisto
Last updated: 02/08/2006
Other names: 1H-Indole-4-ol acetate; Indole-4-ol acetate; Indole-4-yl acetate; 4-Indolyl acetate