ORGN 246 |
| The palladium-catalyzed cross-coupling reaction between different types of organoboron compounds and various organic halides or triflates in the presence of base provides a powerful and general methodology for the formation of carbon-carbon bonds. The (sp3)C-B compounds (alkylboron compounds) and (sp2)C-B compounds (such as aryl- and 1-alkenylboron derivatives) readily cross-couple with organic electrophiles to give coupled products selectively in high yields. Most recently, the (sp)C-B compounds (1-alkynylboron derivatives) have been also observed to react with organic electrophiles to produce expected cross-coupled products. Such coupling reactions offer several advantages: (1) ready availability of reactants (2) mild reaction conditions (3) water stability (4) easy use of the reaction both in aqueous and heterogeneous conditions (5) toleration of a broad range of functional groups (6) high regio- and stereoselectivity of the reaction (7) insignificant effect of steric hindrance (8) use of a small amount of catalysts (9) application in one-pot synthesis (10) nontoxic reaction (11) easy separation of inorganic boron compound As one of defects of the reaction, one would point out the use of bases. However, it could be overcome the difficulty by using suitable solvent systems and adequate bases. Consequently, these coupling reactions have been actively utilized not only in academic laboratories but also in industrial processes. In this lecture, the overview of the coupling reaction will be discussed to understand the whole. |
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H. C. Brown Legacy Symposium
8:30 AM-12:00 PM, Monday, 11 September 2006 Moscone Center -- Room 134, Oral
Division of Organic Chemistry |