Tetrahydroisoquinolines represent a large class of natural compounds with interesting and diverse biological properties. Therefore, these heterocycles are important targets for organic synthesis and much effort has been directed towards the development of efficient enantioselective routes to prepare chiral tetrahydroisoquinolines. The methods investigated thus far include palladium-catalyzed C—H activation of arylethylamines, transition-metal-catalyzed hydro-genation of imines or heteroaromatic compounds, as well as Lewis acid promoted ionic cyclizations, and organo-catalytic Mannich reactions. However, these procedures are limited by the fact that either electron-rich phenyletbyl-amine derivatives are required, or only alkyl groups can be introduced at the stereogenic center, or a number of steps are required to reach the unprotected tetrahydroisoquinoline.
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