Copper-Catalyzed Intermolecular Trifluoromethylazidation of Alkenes: Convenient Access to CF<sub>3</sub>-Containing Alkyl Azides
作者:Fei Wang、Xiaoxu Qi、Zhaoli Liang、Pinhong Chen、Guosheng Liu
DOI:10.1002/anie.201309991
日期:2014.2.10
A novel copper‐catalyzed intermoleculartrifluoromethylazidation of alkenes has been developed under mild reaction conditions. A variety of CF3‐containing organoazides were directly synthesized from a wide range of olefins, including activated and unactivated alkenes, and the resulting products can be easily transformed into the corresponding CF3‐containing amine derivatives.
A range of substituted cycloalkene-1,1-dicarboxylat es was synthesized through olefinmetathesis starting from readily available acylic malonate pre cursors in an efficient fashion. As a metathesis catalyst, a Grubbs II-type catalyst was used in the se experiments, which were run in water and gave the cyclic malonate products with high convers ions of 94-100%. The catalytic amount was in the range
一系列取代的环烯烃-1,1-二羧酸酯是通过烯烃复分解以有效的方式从容易获得的酰基丙二酸酯前体开始合成的。作为复分解催化剂,在这些实验中使用了 Grubbs II 型催化剂,其在水中运行并得到具有 94-100% 高转化率的环状丙二酸产物。取决于起始材料的结构,催化量在0.5-5mol%的范围内。证明了该复分解反应在水中的普遍性及其适用于制备五元和六元和烷基以及芳基取代的前手性环烯烃-1,1 二羧酸酯。
Enantioselective Hydrolysis of Functionalized 2,2-Disubstituted Oxiranes with Bacterial Epoxide Hydrolases
作者:Andreas Steinreiber、Ingrid Osprian、Sandra F. Mayer、Romano V. A. Orru、Kurt Faber
ether-oxygen to the stereogenic quaternary carbon center of the oxirane ring had a profound influence on the enantioselectivity, and several oxiranes were resolved with good to excellent selectivities. The enantiomerically enriched epoxides and vicinal diols thus obtained contain a useful “synthetic handle” in their side chain, which allows their use as buildingblocks in asymmetric synthesis.
The comparative study of two synthetic pathways for nucleoside phosphoantigens is reported herein. The first using esterification of the γ-phosphate of ATP is leading to low yields whereas the coupling of ADP–imidazolate intermediate with a monophosphate counterpart is more efficient. Using this second approach various analogues of ApppI and ApppH were obtained. We have also investigated the synthesis of (E)-2-methyl-4-(hydroxyl)but-2-en-1-ol from mesaconic acid.
An unprecedented copper-catalyzed multicomponent radical-based reaction involving alkenes, P(O)H compounds, sulfur powder, and Togni reagent II at room temperature has been developed. A variety of highly functionalized CF3-containing S-alkyl phosphorothioates can be directly prepared from a wide range of activated and unactivated alkenes. Moreover, this protocol highlights its potential in the late-stage