Stereospecific Stille Cross-Couplings Using Mn(II)Cl<sub>2</sub>
作者:Rambabu Dakarapu、John R. Falck
DOI:10.1021/acs.joc.7b02780
日期:2018.2.2
Cross-coupling reactions are a staple in organic synthesis, especially for C–C bond formation with sp- and sp2-carbon electrophiles. In recent years, the range of accessible C–C bonds has been extended to stereogenic centers which expedites access to greater molecular complexity. However, these reactions predominantly depend upon late transition metal (LTM) catalysts whose cost, toxicity, and/or environmental
Efficient Trifluoromethylation of Activated and Non-Activated Alkenyl Halides by Using (Trifluoromethyl)trimethylsilane
作者:Andreas Hafner、Stefan Bräse
DOI:10.1002/adsc.201100528
日期:2011.11
An efficient method for the trifluoromethylation of halogenated double bonds by using in situ generated “trifluoromethyl copper” is described. Herein, the most common trifluoromethyl source, (trifluoromethyl)trimethylsilane, was converted selectively into “trifluoromethyl copper” by using copper iodide as copper source and potassium fluoride as promoter. In 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone
Copper-Catalyzed Direct Alkenylation of<i>N</i>-Iminopyridinium Ylides
作者:James J. Mousseau、James A. Bull、André B. Charette
DOI:10.1002/anie.200906020
日期:2010.2.1
A versatile Cu‐catalyzed direct CH alkenylation of N‐iminopyridinium ylides, compatible with several different copper sources (including a penny), provides a powerful and inexpensive method for the synthesis of functionalized pyridine derivatives. Chemoselective functionalization of halide‐containing compounds allows the synthesis of alkenyl pyridines containing reactive tethers for further functionalization
substituted benzylic manganese chlorides were prepared by insertion of magnesium turnings in the presence of MnCl2·2LiCl in THF at −5 °C within 2 h. These benzylic manganese reagents underwent smooth cross-couplings with various functionalized alkenyl iodides, bromides, and triflates or iodoacrylates in the presence of 10 mol % FeCl2 at 25 °C for 1–12 h. Mechanistic studies showed that benzylic manganese
Synthesis of 2-Substituted Pyrazolo[1,5-<i>a</i>]pyridines through Cascade Direct Alkenylation/Cyclization Reactions
作者:James J. Mousseau、Angélique Fortier、André B. Charette
DOI:10.1021/ol902710f
日期:2010.2.5
from N-iminopyridinium ylides is described. These medicinally interesting compounds are formed through a cascadeprocess involving a palladium-catalyzed direct alkenylation reaction followed by silver-mediated cyclization. The reaction can be performed with a wide range of electron-poor and electron-rich alkenyl iodides in good yields. This work represents perhaps the most direct route for the preparation
描述了由N-亚氨基吡啶鎓的叶立德合成2-取代的吡唑并[1,5- a ]吡啶。这些医学上有趣的化合物是通过级联过程形成的,该过程涉及钯催化的直接烯基化反应,然后进行银介导的环化反应。该反应可与多种贫电子和富电子的烯基碘化物以高收率进行。这项工作可能代表了制备这些化合物的最直接途径。