Oxidative Addition of Aryl Electrophiles to a Prototypical Nickel(0) Complex: Mechanism and Structure/Reactivity Relationships
Oxidative Addition of Aryl Electrophiles to a Prototypical Nickel(0) Complex: Mechanism and Structure/Reactivity Relationships
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DOI：
10.1021/acs.organomet.7b00208
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发表时间：
2017-04-24
期刊：
影响因子：
2.8
通讯作者：
Nelson, David J.
中科院分区：
文献类型：
--
作者：
Bajo, Sonia;Laidlaw, Gillian;Nelson, David J.
已经对模型 Ni-0 配合物与一系列芳基亲电子试剂的反应进行了详细的动力学研究。反应通过快速配体交换预平衡进行，然后通过氧化加成生成 [(NiX)-X-I(dppf)]（和联芳基）或 [Ni-II(Ar)X(dppf)]；芳基卤的邻位取代基决定了这些可能性之间的选择性。给出了反应性等级，其中一系列底物按照它们进行氧化加成的速率的顺序进行定量排序。氧化加成速率与原型交叉偶联反应中的转化率松散相关。在动力学实验条件下产生 Ni-I 产物的底物。在催化下产生更多的自偶联产物
Detailed kinetic studies of the reaction of a model Ni-0 complex with a range of aryl electrophiles have been conducted. The reactions proceed via a fast ligand exchange pre-equilibrium, followed by oxidative addition to produce either [(NiX)-X-I(dppf)] (and biaryl) or [Ni-II(Ar)X(dppf)]; the ortho substituent of the aryl halide determines selectivity between these possibilities. A reactivity scale is presented in which a range of substrates is quantitatively ranked in order of the rate at which they undergo oxidative addition. The rate of oxidative addition is loosely correlated to conversion in prototypical cross-coupling reactions. Substrates that lead to Ni-I products in kinetic experiments conditions. produce more homocoupling products under catalytic