高氧化态的钯(IV)化合物引起了有机化学界的广泛关注，钯(IV)物种的非β-消除性、快速地还原消除能力和参与亲核进攻反应的能力，以及由此表现出来的化学反应活性与钯(II)物种截然不同；在有机合成反应中，钯(IV)物种往往由Pd(II)物种通过Pd(II)/Pd(IV)的循环原位产生。本项目拟发展基于钯(IV)的有机合成新方法及其在具有生物活性的小分子合成中的应用：利用导向基团辅助的非预活化底物碳氢活化产生的苯(杂)环钯(II)物种，通过降冰片烯与卤代物调节为钯(IV)物种，完成偶联反应后进行再次官能团化，实现化学反应多位点活化，提高原子经济性，合成各类具有生物活性的小分子化合物尤其是环状化合物；利用烯丙基亚胺酯及其类似物原位产生的烷基钯(II)物种，通过氧化剂使其转化为钯(IV)物种，通过还原消除反应以及引入各类亲核试剂进行亲核加成，合成相关的氨基醇、胺和杂环类小分子化合物。

Recently, the chemistry of high-oxidation-state Pd(IV) has received significant attention. The reactivity of Pd(IV) species is much different from Pd(II) species, mainly due to their inherent ability of non β-elimination, fast reductive elimination and participation in nucleophilic attack reaction. Generally, Pd(IV) species involved in organic synthesis are in situ generated from Pd(II) species. We proposed that the aryl Pd(II) intermediates formed in directing group (DG)-assisted C?H activation of arenes and heterocycles would be rich sources of Pd(II) species, and could transform to Pd(IV) species via norbornene (NB) and halides mediated reaction. The generated Pd(IV) species would take reductive elimination to be functionalized Pd(II) species, which could be subject to further functionalization. This would lead to multi-reactivity of chemicals，atom economy improvement and also could be utilized to synthetic application of various bioactive small molecules especially cyclic compounds. Another proposal is that the alkyl Pd(II) intermediates formed in aminopalladation of allylic imidates could be oxidized to Pd(IV) species, which could take reductive elimination or be intercepted by external nucleophiles for access to various aminoalcohols, amines and heterocycles.