π-Acidic alkene ligand effects in Pd-catalysed cross-coupling processes: exploiting the interaction of dibenzylidene acetone (dba) and related ligands with Pd(0) and Pd(II)
π-Acidic alkene ligand effects in Pd-catalysed cross-coupling processes: exploiting the interaction of dibenzylidene acetone (dba) and related ligands with Pd(0) and Pd(II)
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DOI：
10.1039/b811772a
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发表时间：
2008-10-21
影响因子：
3.2
通讯作者：
Fairlamb, Ian J. S.
中科院分区：
文献类型：
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作者：
Fairlamb, Ian J. S.
酸性烯烃（烯烃）配体积极影响钯催化的交叉偶联过程，与钯(0)和钯（II）物种相互作用，在某些情况下稳定关键的催化中间体。氧化加成和还原消除速率都受到影响。在某些情况下，酸性烯烃可以减缓对氢的消除，这开辟了新的反应途径（例如，由适当的亲核试剂拦截sigma-烷基钯（II））。-酸性烯烃配体可以单独作用，也可以与另一种双电子供体配体（如胺、膦或n -杂环碳）协同作用。这篇透视文章的目的是强调使用-酸性烯烃配体可以获得的令人印象深刻的结果，特别关注二苄基丙酮（dba）衍生物。其他类型的烯烃配体，如大环烯烃，也进行了讨论。
pi-Acidic alkene (olefin) ligands positively influence Pd-catalysed cross-coupling processes, interacting with both palladium(0) and palladium(II) species, in some cases stabilising key catalytic intermediates. Rates of oxidative addition and reductive elimination are both affected. In certain cases, P-hydrogen elimination can be slowed down by pi-acidic alkenes, which opens up new reaction pathways (e.g. interception of sigma-alkylpalladium(II) species by appropriate nucleophiles). pi-Acidic alkene ligands can act independently or in a synergistic fashion with another two-electron donor ligand (e.g. amine, phosphine or N-heterocyclic carbene). The purpose of this perspective article is to highlight the impressive results that can be obtained using pi-acidic alkene ligands, with a particular focus on dibenzylidene acetone (dba) derivatives. Other types of alkene ligands, e.g. macrocyclic alkenes, are also discussed.