Synthesis of Tetrahydroisoquinolines via Cascade Reductive Amination of Isochromenylium Tetrafluoroborate with Primary Amines

Abstract

Reactions of isochromenylium tetrafluoroborates with various primary amines have been investigated under reductive amination conditions. The established cascade methodology provides a convenient one-step synthesis of various tetrahydroisoquinoline derivatives under mild conditions.

Key words

isochromenylium - reductive amination - tetrahydroisoquinoline - heterocycle - cascade reaction

References

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17

Two diastereomeric isomers were observed in ^¹³C NMR spectrum of 4c (all carbon peaks are reported in the experimental section), but they were homogeneous in the ^¹H NMR spectrum.