Manufacturing Process
A mixture of 5 parts of 3-(2'-ethyl-2'-nitrovinyl)indole in 80 parts of ethanol
saturated with ammonia gas is shaken in an atmosphere of hydrogen at 100
atmospheres pressure and at 20°C in the presence of 1 part of a 5%
palladium on carbon catalyst until the theoretical amount of hydrogen is
absorbed. The catalyst is removed by filtration. The ethanol and ammonia are
then removed from the filtrate by distillation under reduced pressure. The
residual oil is dissolved in 170 parts of dry ether, 50 parts of potassium
hydroxide pellets are added and the solution is kept at 18°C to 22°C for 2
hours. The mixture is filtered and hydrogen chloride is passed into the filtrate
to precipitate crude (α-ethyltryptamine hydrochloride. This is purified by
crystallization from methanol/ethyl acetate and it then has a MP of 221°C.
