17β-Isopropylsparteine and 17β-Isopropyllupanine Perchlorates

Abstract

In the sparteine derivative, (1), C18H34N22+.2ClO4- {sparteine = [7S-(7α,7aα,14α,14aβ)]-dodecahydro-7,14-methano-2H,6H-dipyrido[1,2-a: 1′,2′-e][1,5]diazocine}, the quinolizidine skeletons (A/B and C/D systems) have trans/trans configuration with chair, chair, distorted boat and chair conformations for the A, B, C and D rings, respectively. In the lupanine derivative, (2), C18H31N2O+.ClO4-.H2O {lupanine = dodecahydro-7,14-methano-4H, 6H-dipyrido[1,2 -a:1′,2′-e][1,5]diazocin-4-one}, the configuration of the cation is quasi-trans and trans for A/B and C/D ring systems, respectively, and the ring conformations are intermediate between sofa and half-chair, chair, distorted boat and chair for the A, B, C and D rings, respectively. In both (1) and (2) bulky isopropyl substituents are responsible for large deformations of the bisquinolizidine skeletons. Hydrogen bonds play a major role in crystal packing.