Enantiopure tetrahydro-β-carbolines via Pictet-Spengler reactions with N-sulfinyl tryptamines

The influence of N-sulfinyl chiral auxiliaries on the stereochemistry of the Pictet-Spengler reaction has been investigated. From enantiopure (R)-N-beta-toluenesulfinyltryptamine a new and efficient route to enantiopure tetrahydro-beta-carbolines has been established.