1-(2-Pyridyl)-2-propen-1-ol, obtained by vinylation of commercially available picolinaldehyde, resulted a good starting material for the synthesis of the indolizidine skeleton. In particular, a simple process involving bromination, reduction, and nucleophilic substitution (via elimination and addition) allowed an easy conversion of the starting material into (±)-lentiginosine in ~27% overall yield.

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CALAMAI, E.; SALVINI, A.; GIOMI*, D.; Tetrahedron 69 (2013) 16, 3475-3479, http://dx.

Synthesis of 1,2-Dihydroxyindolizidines from 1-(2-Pyridyl)-2-propen-1-ol. -Treatment of the propenol (I) with bromine followed by reduction and hydroxylation allows a facile access to 1,2-dihydroxyindolizidines. Additionally, it is shown that reaction of the indolizidine (IV) with NaI yields the iodides (VIII) and (IX), while the diastereomer (V) provides the iodides (X) and (XI). -(GIOMI*, D.; ALFINI, R.; MICOLI, A.; CALAMAI, E.; FAGGI, C.; BRANDI, A.; J. Org. Chem. 76 (2011) 22, 9536-9541, http://dx.doi.org/10.1021/jo201830b ; Dip. Chim. Org. Ugo Schiff, Univ. Stud. Firenze, I-50019 Sesto Fiorentino, Italy; Eng.) -Jannicke 12-158