Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, USA.
J Am Chem Soc. 2009 Nov 4;131(43):15618-20. doi: 10.1021/ja905816q.
This communication describes studies of oxidatively induced C-C bond-forming reductive elimination from ((t)Bu(2)bpy)Pd(II)(Me)(2). With the outer-sphere oxidant ferrocenium, the data are consistent with a mechanism involving Pd(III) and Pd(IV) intermediates, with C-C bond formation occurring from the latter. The reaction with Ag(+) appears to proceed via a Pd-Ag(+) adduct, which then undergoes inner sphere electron transfer to generate Pd(III). In contrast, the slower benzoquinone reaction forms ethane by a different pathway that does not involve methyl group scrambling and generates Pd(0) products.
本通讯描述了 ((t)Bu(2)bpy)Pd(II)(Me)(2) 中氧化诱导的 C-C 键形成还原消除反应的研究。在外球氧化剂铁氰化钾的作用下,数据与涉及 Pd(III) 和 Pd(IV) 中间体的反应机理一致,C-C 键的形成来自后者。与 Ag(+) 的反应似乎通过 Pd-Ag(+) 加合物进行,然后通过内球电子转移生成 Pd(III)。相比之下,较慢的苯醌反应通过不涉及甲基 scrambling 的不同途径生成乙烷,并生成 Pd(0) 产物。