作者：Yazhou Ding, Qiang-Qiang Ma, Jiaxin Kang, Jie Zhang, * Shujun Li  and Xuenian Chen *

A Pd(II) chloride complex supported by a Yamashita–Nozaki PBP pincer ligand, [C6H4-1,2-(NCH2PtBu2)2B]PdCl (1a), was synthesized. The structure, properties and catalytic activity of complex 1a were compared with those of the corresponding POCOP pincer complex [C6H3-2,6-(OPtBu2)2]PdCl (2a). It was found that the Pd centre in complex 1a is more electron rich and easier to be oxidized than that in complex 2a; complex 1a is a much better catalyst for Suzuki–Miyaura cross-coupling reactions than complex 2a. Starting from complexes 1a and 2a, two series of Pd(II) pincer complexes bearing a SH, BH4, N̲CS, N̲CSe or N3 covalent ligand, [C6H4-1,2-(NCH2PtBu2)2B]PdY (Y = SH, 1b; BH4; 1c; N̲CS, 1d; N̲CSe, 1e; and N3, 1f) and [C6H3-2,6-(OPtBu2)2]PdY (Y = SH, 2b; BH4, 2c; N̲CS, 2d; N̲CSe, 2e; and N3, 2f), were synthesized and fully characterized. Single crystal X-ray diffraction analysis indicated that the Pd centre is less tightly chelated in PBP pincer complexes. The strong σ-donor ability of the PBP pincer ligand has little influence on the structure of the covalent ligand possessing both σ-donor and π-acceptor properties. However, the stretching vibrational frequencies of N̲CS, N̲CSe and N3 ligands and the coordination mode of the BH4 ligand are significantly different in these two types of palladium pincer complexes.

 

期刊年卷期页码：Dalton Trans., 2019,48, 17633-17643 

链接地址：http://dx.doi.org/10.1039/C9DT03954F