Photocatalytic Hydrodefluorination: Facile Access to Partially Fluorinated Aromatics
作者:Sameera M. Senaweera、Anuradha Singh、Jimmie D. Weaver
DOI:10.1021/ja500031m
日期:2014.2.26
science as well as the pharmaceutical and agrochemical industries and yet are often difficult to access. This Communication describes a photocatalytic hydrodefluorination approach which begins with easily accessible perfluoroarenes and selectively reduces the C-F bonds. The method allows facileaccess to a number of partially fluorinated arenes and takes place with unprecedented catalytic activity
Zirconocene Dichloride Catalyzed Hydrodefluorination of C sp 2F bonds
作者:Shuhui Yow、Sarah J. Gates、Andrew J. P. White、Mark R. Crimmin
DOI:10.1002/anie.201207036
日期:2012.12.7
A two‐metal job: Four‐coordinate aluminum dihydrides such as 1 are reported as terminal reductants for the selective title reaction. The heterobimetallic complex 2 has been isolated and shown to be catalytically competent.
potassium formate is described. With the aid of metal/NH cooperation, the C–N chelating Ir complexes derived from benzylic amines can efficiently promote the reduction involving the C–F bond cleavage under ambient conditions even in the absence of hydrosilanes or H2 gas, leading to the partiallyfluorinated products in good yields and with high selectivity.
Competition of Nucleophilic Aromatic Substitution, σ-Bond Metathesis, and <i>syn</i>
Hydrometalation in Titanium(III)-Catalyzed Hydrodefluorination of Arenes
Turnover numbers of up to 93 were observed. Solution density functional theory calculations at the M06‐2X/TZ(PCM)//M06‐2X/TZ(PCM) level of theory provided insight into the mechanism of TiIII‐catalyzed aromatic hydrodefluorination. Two different substrate approaches, with a Ti–F interaction (pathway A) and without a Ti–F interaction (pathway B), are possible. Pathway A leads to a σ‐bond metathesis transition
“π-Hole−π” Interaction Promoted Photocatalytic Hydrodefluorination via Inner-Sphere Electron Transfer
作者:Jingzhi Lu、Navneet S. Khetrapal、Jacob A. Johnson、Xiao Cheng Zeng、Jian Zhang
DOI:10.1021/jacs.6b08620
日期:2016.12.14
promotes the electron transfer against unfavorable energetics (ΔGET up to 0.63 eV) and initiates the subsequent HDF. The sterichindrance of Py and FA largely dictates the HDF reaction rate, pointing to an inner-sphere electron transfer pathway. This work highlights the importance of the size and shape of the photocatalyst and the substrate in controlling the electron transfermechanism and rates as well
我们描述了使用芘基光催化剂 (Py) 的多氟芳烃 (FA) 的无金属光催化加氢脱氟 (HDF)。Py 和 FA 之间微弱的“π-空穴-π”相互作用促进了针对不利能量的电子转移(ΔGET 高达 0.63 eV)并启动随后的 HDF。Py 和 FA 的空间位阻在很大程度上决定了 HDF 反应速率,指向内部球体电子转移途径。这项工作强调了光催化剂和基材的尺寸和形状在控制电子转移机制和速率以及整个光催化过程中的重要性。