Landa Aitor, Minkkilä Anna, Blay Gonzalo, Jørgensen Karl Anker
Danish National Research Foundation, Center for Catalysis, Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark.
Chemistry. 2006 Apr 24;12(13):3472-83. doi: 10.1002/chem.200501475.
A new, short, and simplified procedure for the synthesis of optically active pyridine derivatives from pro-chiral pyridine-N-oxides is presented. The catalytic and asymmetric Mukaiyama aldol reaction between ketene silyl acetals and 1-oxypyridine-2-carbaldehyde derivatives catalyzed by chiral copper(II)-bis(oxazoline) complexes gave optically active 2-(hydroxyalkyl)- and 2-(anti-1,2-dihydroxyalkyl)pyridine derivatives in good yields and diastereoselectivities, and in excellent enantioselectivities-up to 99 % enantiomeric excess. As a synthetic application of the developed method, a full account for the asymmetric total synthesis of a nonnatural indolizine alkaloid is provided.
本文介绍了一种从手性前体吡啶 - N - 氧化物合成光学活性吡啶衍生物的新的、简短且简化的方法。在手性铜（II）- 双（恶唑啉）配合物催化下，烯酮硅基缩醛与1 - 氧代吡啶 - 2 - 甲醛衍生物之间的催化不对称Mukaiyama羟醛缩合反应，以良好的产率和非对映选择性，以及优异的对映选择性（对映体过量高达99%）得到了光学活性的2 - （羟烷基） - 和2 - （反式 - 1,2 - 二羟基烷基）吡啶衍生物。作为所开发方法的合成应用，还提供了一种非天然中氮茚生物碱的不对称全合成的完整过程。
