ChemInform Abstract: Removal of the Pyrrolidine Substituent by Dehydrogenation of 4‐ Pyrrolidin‐2‐yl‐3,4‐dihydro‐ and 1,2,3,4‐tetrahydroisoquinolines.

Abstract

Removal of the Pyrrolidine Substituent by Dehydrogenation of 4-Pyrrolidin-2-yl-3,4-dihydro-and 1,2,3,4-tetrahydroisoquinolines.-Pyrrolidinyl groups located at C-4 of 3,4-dihydro-or 1,2,3,4-tetrahydroisoquinolines, respectively, are lost in the course of dehydrogenation of these isoquinoline derivatives. A N-methylpyrrole ring at C-4 does not interfere with dehydrogenation of the isoquinoline system (cf. (V), (VII)). Acyclically substituted isoquinolines, hydrogenated in ring B, e.g. (X), show loss of the amine group by benzylic cleavage, affording compound (IX). Scope and limitation of this reaction are determined (yields in part not given or in g). -(MAHBOOBI, S.; KARCHER, A.; GROTHUS, G.; WAGNER, W.; WIEGREBE, W.; Arch.