烯烃是合成许多化学品的重要原料，但简单烯烃的应用受局限较大，解决此问题的途径是烯烃预官能化。烯烃官能化及转化是目前有机合成化学研究领域的热点课题之一。通过在烯烃分子中引入活化基团或可转化基团来改变烯烃的反应性，可以大大拓展烯烃在合成化学中的应用。本申请项目拟通过合理设计、合成高度极化的烯烃分子，即alpha-(硫)羰基N,S-缩烯酮，在烯烃分子中引入(硫)羰基、烷硫基、胺基、炔基和烯基等官能团，赋予这些极化烯烃分子多反应性，研究其与卡宾(醛腙)、硫叶立德、高价碘试剂、重氮盐、单质硫和联烯等的反应；结合对催化剂体系的考察、辅助理论计算，研究相关反应的机理，探索合成反应的本质。尽可能不使用过渡金属试剂，由此发展利用N,S-官能化烯烃直接、高效地合成有机功能分子的新的绿色有机合成方法学。

Alkenes are important starting materials for many synthetic chemicals, but simple alkenes are limited to be applied in synthetic chemistry. To solve this problem, alkenes have to be prefunctionalized. Functionalization of alkenes is one of the hot topics in organic chemistry. The reactivity of alkenes can be improved by means of introducing activating and transformable groups on their backbones, which makes the resultant prefunctionalized alkenes be widely applied in organic synthesis. In the present application, we plan to design and synthesize highly polarized alkenes, that is, alpha-oxo (thioxo) ketene N,S-acetals, by introduction of C=O, C=S, alkylthio, amido, alkynyl, and/or alkenyl functionalities to the olefinic C=C bond, bestowing these polarized alkenes with multiple reactivities. Their reactions with carbenes (aldehyde hydrazones), sulfur ylides, hypervalent iodine reagents, aryl diazonium salts, elemental sulfur, and allenes will be investigated. The reaction mechanisms will also be studied through exploration of the catalyst systems with the aid of DFT calculations. No transition-metal reagents will be used in the reactions as possible as we can. Thus, we will develop new green direct and efficient N,S-functionalized alkene-based synthetic methodologies for diverse functionalized organic molecules.