172277-65-5Relevant academic research and scientific papers
A concise asymmetric route to the bridged bicyclic tropane alkaloid ferruginine using enyne ring-closing metathesis
Aggarwal, Varinder K.,Astle, Christopher J.,Rogers-Evans, Mark
, p. 1469 - 1471 (2007/10/03)
Enyne metathesis has been used to prepare bridged azabicycles and applied in a short asymmetric synthesis of the tropane ferruginine. A Grubbs first generation catalyst proved to be superior to the second generation catalyst in the enyne metathesis reaction.
A new divergent synthesis of (+)- and (-)-ferruginine utilizing PLE-catalyzed asymmetric dealkoxycarbonylation
Katoh, Takahiro,Kakiya, Kiyoshi,Nakai, Takashi,Nakamura, Soichi,Nishide, Kiyoharu,Node, Manabu
, p. 2351 - 2358 (2007/10/03)
A new divergent synthesis of (+)- and (-)-ferruginine 4, via the optically active 8-benzyl-3-oxo-8-azabicyclo[3.2.1]octane-2-carboxylates 6 is described. The β-keto ester intermediates 6 were prepared by a novel PLE-catalyzed asymmetric dealkoxycarbonylation of the symmetric tropinone-type diesters 5. The key problem in the synthesis is controlling the regioselectivity of the reaction at the 2- and 4-positions in the tropane framework of the β-keto ester 6 for introduction of the acetyl group.
Enantioselective synthesis of functionalized tropanes by rhodium(II) carboxylate-catalyzed decomposition of vinyldiazomethanes in the presence of pyrroles
Davies, Huw M. L.,Matasi, Julius J.,Mark Hodges,Huby, Nicholas J. S.,Thornley, Craig,Kong, Norman,Houser, Jeffrey H.
, p. 1095 - 1105 (2007/10/03)
A series of enantiomerically enriched tropanes was synthesized by the rhodium(II) octanoate-catalyzed reaction of various N-BOC-protected pyrroles with vinyldiazomethanes. The overall 3 + 4 annulation occurs by a tandem cyclopropanation/Cope rearrangement. Asymmetric induction was best achieved in these transformations by using either (S)-lactate or (R)-pantolactone as a chiral auxiliary on the vinyldiazomethanes. Reactions carried out with the chiral catalyst tetrakis-[N-(4-tert-butylbenzenesulfonyl)-(L)-prolinato]dirhodium (2) provided moderate asymmetric induction, but also resulted in the formation of isomeric azabicyclooctane side products. The utility of the synthetic process was demonstrated through the asymmetric synthesis of (-)-anhydroecgonine methyl ester and (-)-ferruginine.
Enantiospecific synthesis of (+)- and (-)-ferruginine from L-glutamic acid. Synthesis of tropanes via intramolecular iminium ion cyclization
Hernandez, Andres S.,Thaler, Adrian,Castells, Josep,Rapoport, Henry
, p. 314 - 323 (2007/10/03)
Iminium ions, generated by decarbonylation of N-benzyl-5-[1-(methoxycarbonyl)-4-oxopentyl]prolines, undergo intramolecular cyclization to afford 2,4-disubstituted tropanes in good yields. This transformation is also shown to be a stereospecific reaction. The value of these substituted tropanes has been demonstrated by functional group manipulation, leading to the enantiospecific synthesis of (±)-ferruginine, an alkaloid isolated from Darlinga ferruginea, and its unnatural enantiomer, (-)-ferruginine.
