作者:Douglas C. Behenna、Justin T. Mohr、Nathaniel H. Sherden、Smaranda C. Marinescu、Andrew M. Harned、Kousuke Tani、Masaki Seto、Sandy Ma、Zoltán Novák、Michael R. Krout、Ryan M. McFadden、Jennifer L. Roizen、John A. Enquist、David E. White、Samantha R. Levine、Krastina V. Petrova、Akihiko Iwashita、Scott C. Virgil、Brian M. Stoltz
DOI:10.1002/chem.201003383
日期:2011.12.9
functions with nearly identical efficiency in terms of yield and enantioselectivity. Catalyst discovery and development, the optimization of reaction conditions, the exploration of reactionscope, and applications in target‐directed synthesis are reported. Experimental observations suggest that these alkylationreactions occur through an unusual inner‐sphere mechanism involving binding of the prochiral
A novel selective fragmentation of cycloalkanones by NaNO2/HCl has been established. The C–Cbond cleavage reaction proceeds smoothly under mild conditions, selectively affording versatile keto acids or oxime acids. The methodology can streamline the synthesis of valuable chiral molecules and isocoumarins from readily available feedstocks.
A Redox Strategy for Light-Driven, Out-of-Equilibrium Isomerizations and Application to Catalytic C–C Bond Cleavage Reactions
作者:Eisuke Ota、Huaiju Wang、Nils Lennart Frye、Robert R. Knowles
DOI:10.1021/jacs.8b12552
日期:2019.1.30
We report a general protocol for the light-driven isomerization of cyclic aliphatic alcohols to linear carbonyl compounds. These reactions proceed via proton-coupled electron-transfer activation of alcohol O-H bonds followed by subsequent C-C β-scission of the resulting alkoxy radical intermediates. In many cases, these redox-neutral isomerizations proceed in opposition to a significant energetic gradient
我们报告了光驱动的环状脂肪醇异构化为线性羰基化合物的通用协议。这些反应通过醇 OH 键的质子耦合电子转移活化进行,随后生成的烷氧基自由基中间体的 CC β 断裂。在许多情况下,这些氧化还原中性异构化与显着的能量梯度相反,产生的产品热力学稳定性低于起始材料。提出了一种机制来合理化这种不平衡行为,该机制可以作为设计由激发态氧化还原事件驱动的其他逆热力学转换的模型。
A Convenient Synthesis of Acyclic 1,n-Diketones (n = 5-8) from 2-<i>t</i>-Butylperoxycycloalkanones
作者:Akira Nishinaga、Katsuhiko Rindo、Teruo Matsuura
DOI:10.1055/s-1986-31866
日期:——
The reaction of organolithium with 2-alkyl-2-t-butylperoxycycloalkanones, readily available from t-butylperoxylation of 2-alkylcycloalkanones, gave 2-t-butylperoxy-1-cycloalkanol derivatives quantitatively, thermal decomposition of which with or without an acid afforded 1,n-diketones (n = 5-8) in excellent yields.
Catalytic Radical–Polar Crossover Reactions of Allylic Alcohols
作者:Eric E. Touney、Nicholas J. Foy、Sergey V. Pronin
DOI:10.1021/jacs.8b12075
日期:2018.12.12
Radical-polarcrossover hydrofunctionalizations of tertiary allylic alcohols are described. Depending on the structure of the catalyst, corresponding epoxides or semipinacol rearrangement products are selectively obtained in good yields. Experimental evidence points to the participation of alkylcobalt complexes as electrophilic intermediates.