Wang Qing, Jung Hoimin, Kim Dongwook, Chang Sukbok
Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, South Korea.
Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, South Korea.
J Am Chem Soc. 2023 Oct 31. doi: 10.1021/jacs.3c09679.
Hydroamination facilitated by metal hydride catalysis is an appealing synthetic approach to access valuable nitrogen-containing compounds from readily available unsaturated hydrocarbons. While high regioselectivity can be achieved usually for substrates bearing polar chelation groups, the reaction involving simple alkenes frequently provides nonselective outcomes. Herein, we report an iridium-catalyzed highly regioselective terminal C(sp)-H amidation of internal alkenes utilizing dioxazolones as an amino source via olefin chain walking. Most notably, this mechanistic motif of double bond migration to the terminal position operates not only with dialkyl-substituted simple alkenes including styrenes but also with heteroatom-substituted olefins such as enol ethers, vinyl silanes, and vinyl borons, thus representing the first example of the terminal methyl amidation of the latter type of alkenes through a nondissociative chain walking process.
金属氢化物催化促进的氢胺化反应是一种从易得的不饱和烃制备有价值的含氮化合物的有吸引力的合成方法。虽然对于带有极性螯合基团的底物通常可以实现高区域选择性,但涉及简单烯烃的反应常常产生非选择性结果。在此,我们报道了一种铱催化的、利用二恶唑酮作为氨基源通过烯烃链行走实现的内烯烃的高度区域选择性末端C(sp)-H酰胺化反应。最值得注意的是,这种双键迁移到末端位置的机理模式不仅适用于包括苯乙烯在内的二烷基取代的简单烯烃,也适用于杂原子取代的烯烃,如烯醇醚、乙烯基硅烷和乙烯基硼,因此代表了通过非解离链行走过程实现后一类烯烃末端甲基酰胺化的首个例子。