α－双官能化胂、碲叶立德的合成及其在立体选择合成中应用

We firstly found thatα-fluorochalcones can be synthesized by the Wittig reaction of α-fluoro functionalized ylide stereoselectively in good yields and with high E form. As the first example of the application ofα-functionalized telluronium ylide in organic synthesis, (Z)-α-halo-α, β-unsaturated esters are symthesized by the Wittig-type reaction ofα-halo functionalized telluronium ylide in good yieds and with high stereoselectivities. We also found that a-hypervalent iodine functionalized phosphonium and arsonium ylides can be used as umpolung ylides to react with nucleophiles to give a-heteroatom substituted ylides. Their nucleophilic substitution - Wittig tandem reaction can occur smoothly, affording an efficient method for the stereoselective synthesis of (Z)- a-halo-a, β-unsaturated esters.

高选择性反应的开发是有机合成化学研究的重要课题。胂碲叶立德具有独特的反应性能，在原有工作基础上将多种官能团导入胂碲叶立德的α位，以期发挥复能有机化合物多样化反应性的特点，不仅可藉Wittig反应合成官能团取代烯烃，而且进一步利用官能团的转换开发多取代烯烃的立体选择合成法。这不仅有推动学科发展的科学意义，而且有广阔的应用前景。.