Synthesis of S (+) and R (‐)‐3‐(2‐aminopropyl)indole from ethyl‐ D ‐ and L ‐tryptophanate

A stereospecific requirement for hallucinogenesis applies to certain molecules containing an asymmetric center. Thus, only the R ‐isomers of substituted phenylisopropylamines and lysergic acid diethylamide are psychotomimetic. The enantiomers of a minor hallucinogen, S (+)‐ and R (‐)‐3‐(2‐aminopropyl)indole (α‐methyltryptamine) ( 6a and 6b ) were synthesized via a 5‐step manipulation from D ‐ and L ‐tryptophan ethyl ester hydrochloride, respectively. Optical purity of these two isomers was determined by pmr spectroscopy of their complexes with a europium chiral shift reagent using the indole C 2 H signal.