Amat Tusón, MercedesSemak, VladislavEscolano Mirón, CarmenMolins i Grau, EliesBosch Cartes, Joan2019-01-282019-01-2820121477-0520https://hdl.handle.net/2445/127646A practical enantioselective protecting group-free four-step route to the key quinolizidinone 6 from phenylglycinol-derived bicyclic lactam 1 is reported. The Grignard addition reaction to 6 takes place stereoselectively to give 1-ethyl-4-substituted quinolizidines 4-epi-207I and 7-9. Following a similar synthetic sequence, 9a-epi-6 is also accessed. However, the addition of Grignard reagents to 9a-epi-6 proceeds in a non-stereoselective manner. In order to gain insight into the different stereochemical outcome in the two series, theoretical calculations on the iminium salts A and B have been performed. The study concludes that the addition of the hydride, which is the step that determines the configuration of the final products, occurs in a stereoelectronic controlled manner. The theoretical study is in agreement with the experimental results.10 p.application/pdfeng(c) Amat Tusón, Mercedes et al., 2012AlcaloidesSíntesi asimètricaSíntesi orgànicaCompostos bioactiusAlkaloidsAsymmetric synthesisOrganic synthesisBioactive compoundsinfo:eu-repo/semantics/article6139562019-01-28info:eu-repo/semantics/openAccess