Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States.
J Org Chem. 2023 Feb 17;88(4):2648-2654. doi: 10.1021/acs.joc.2c02859. Epub 2023 Feb 8.
AIBN is a convenient electrophilic cyanation reagent for transforming ArLi into ArCN under mild conditions. The addition/fragmentation cascade is controlled by Li···N chelation in which AIBN nitrogens assist in the nearly barrierless fragmentation into the desired ArCN product. Acidic C-H bonds in the fragmented byproduct partially consume ArLi by protonation. Density functional theory calculations and isotopic labeling probe the mechanism and explain the switch to substituted hydrazones in reactions with BuLi.
AIBN 是一种方便的亲电氰化试剂，可在温和条件下将 ArLi 转化为 ArCN。加成/碎裂级联反应受 Li···N 螯合控制，其中 AIBN 氮原子有助于几乎无势垒地碎裂生成所需的 ArCN 产物。碎裂副产物中的酸性 C-H 键通过质子化部分消耗 ArLi。密度泛函理论计算和同位素标记探针研究了该反应的机理，并解释了与 BuLi 反应时向取代腙的转变。
