Total synthesis of (-)-cephalotaxine was achieved from D-(+)-proline by a short sequence of steps. The key intermediate, 1-azaspiro[4.4]nonane, was prepared from vinyl iodide, using stannyl anion generated from Me(3)SiSnBu(3) and CsF, in good yield.
Total synthesis of (-)-cephalotaxine was achieved from D-(+)-proline by a short sequence of steps. The key intermediate, 1-azaspiro[4.4]nonane, was prepared from vinyl iodide, using stannyl anion generated from Me(3)SiSnBu(3) and CsF, in good yield.