Comparative study of the vibrational optical activity techniques in structure elucidation : the case of galantamine

The absolute configuration of the alkaloid galantamine was studied using a range of solution-state techniques; nuclear magnetic resonance (NMR), vibrational circular dichroism (VCD), and Raman optical activity (ROA). While the combined use of NMR and VCD does provide a fast, high-resolution methodology for determining the absolute configuration of galantamine, both techniques were needed in concert to achieve this goal. ROA, on the other hand, proved to be sensitive enough to assign the full absolute configuration without relying on other techniques. In both cases, statistical validation was applied to aid the determination of absolute configuration. In the case of galantamine, ROA combined with statistical validation is shown to be a powerful stand-alone tool for absolute configuration determination

Conjugate addition of 2-(bromomethyl)- and 2-(2-bromoethyl)piperidine to alkyl acrylates : application towards the synthesis of 2-(methoxycarbonyl)indolizidine

Conjugate addition of 2-(bromomethyl)- and 2-(2-bromoethyl)piperidine hydrobromide to methyl and ethyl acrylate in the presence of triethylamine afforded the corresponding 3-[2-(bromomethyl)piperidin-1-yl]propanoates and 3-[2-(2-bromoethyl)piperidin-1-yl]propanoates for the first time. Furthermore, methyl 3-[2-(bromomethyl)piperidin-1-yl]propanoate was converted into the novel 2-(methoxycarbonyl)indolizidine upon treatment with lithium diisopropylamide in THF. The latter ester was easily reduced by means of lithium aluminium hydride in diethyl ether, affording 2-(hydroxymethyl)indolizidine in high yield

ChemInform Abstract: Carbon-Carbon Bond Formation via a Tandem Cationic 2-aza-Cope Rearrangement-Lewis Acid Promoted Petasis Reaction

info:eu-repo/semantics/publishe

ChemInform Abstract: Carbon-Carbon Bond Formation via a Tandem Cationic 2-aza-Cope Rearrangement-Lewis Acid Promoted Petasis Reaction.

info:eu-repo/semantics/publishe