An alternative strategy to the Pictet-Spengler method for tetrahydroisoquinoline synthesis: a feasibility study

Acid-catalysed cyclisations of the 2-aminoethyl styrene derivatives 9 give good to excellent yields of the corresponding tetrahydroisoquinolines 7 by an intramolecular hydroamination reaction, which represents an alternative and potentially more flexible strategy to the classical Pictet–Spengler method for the syntheses of such heterocycles.