A new stereoselective method for the synthesis of (E)-β-arylvinyl iodides and (E)- or (Z)-β-arylvinyl bromides from styrenes and vinyl boronates on the basis of a one-pot procedure via borylative coupling/halodeborylation is reported. Depending on the halogenating agent as well as the mode of the halodeborylation reaction, (E) or (Z) isomers are selectively formed.
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
(<i>Z</i>)-Selective Takai olefination of salicylaldehydes
作者:Stephen M Geddis、Caroline E Hagerman、Warren R J D Galloway、Hannah F Sore、Jonathan M Goodman、David R Spring
DOI:10.3762/bjoc.13.35
日期:——
The Takai olefination (or Takai reaction) is a method for the conversion of aldehydes to vinyl iodides, and has seen widespread implementation in organic synthesis. The reaction is usually noted for its high (E)-selectivity; however, herein we report the highly (Z)-selective Takai olefination of salicylaldehyde derivatives. Systematic screening of related substrates led to the identification of key
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。