is easily accessible by cyclocondensation of δ-oxoester 1 with (R)-phenylglycinol, a three-step synthetic route to enantiopure 1-substitutedtetrahydroisoquinolines, including 1-alkyl-, 1-aryl-, and 1-benzyltetrahydroisoquinoline alkaloids, as well as the tricyclic alkaloid (–)-crispine A, has been developed. The key step is a stereoselective α-amidoalkylation reaction using the appropriate Grignard