Fischer Reaction with 2‐Perfluoroalkylated Cyclic Imines ― An Efficient Route to 2‐Perfluoroalkyl‐Substituted Tryptamines and Their Derivatives and Homologues

Abstract

AbstractThe reaction of 2‐perfluoroalkyl‐substituted cyclic imines with arylhydrazines was investigated. We found that 2‐perfluoroalkylated cyclic imines are highly reactive electrophiles that form, through ring opening, the corresponding hydrazones bearing an amine group at the end of the alkyl chain. Subsequent acidic treatment resulted in a Fischer rearrangement. Thus, a new synthesis of 2‐perfluoroalkylated tryptamines and their homologues through a Fischer reaction was developed. The possibility of modification of the indole core of the 2‐CF3‐substituted tryptamine products was demonstrated, and various 2‐trifluoromethylated tryptamines substituted at the 5‐position were prepared.