含间三联苯骨架的NCN二亚胺钯钳形配合物的合成与结构研究

Synthesis and structural studies of NCN diimine palladium pincer complexes bearing m-terphenyl scaffolds.

作者信息

Ma Liqing, Imbesi Philip M, Updegraff James B, Hunter Allen D, Protasiewicz John D

机构信息

Department of Chemistry, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, USA.

出版信息

Inorg Chem. 2007 Jun 25;46(13):5220-8. doi: 10.1021/ic062476a. Epub 2007 Jun 1.

DOI:10.1021/ic062476a

PMID:17539629

Abstract

The reaction of 2,6-2-{RN=C(H)}C(6)H(4)C(6)H(3)I [R = Ph (4), Cy (5), 2,6-Me(2)C(6)H(3) (6), 2,4,6-Me(3)C(6)H(2) (7), (S)-alpha-methylbenzyl (8)] with Pd(2)(dba)(3) afforded the NCN diimine pincer palladium complexes [2,6-2-{RN=C(H)}C(6)H(4)C(6)H(3)PdI] (9-13) by oxidative addition of the C-I bonds of the ligand precursors. Single-crystal X-ray diffraction analyses of complexes 9-13 reveal formal C(2)-symmetric environments. Variable-temperature NMR studies of complexes 11 and 12 show hindered rotation about the N-Ar bonds and also suggest that atropisomers of complexes 9-13 do not interconvert on the NMR time scale. Consistent with this proposal, isolation of the two possible isomers of 13 (13a and 13b) was possible, and their structures and NMR properties have been examined in detail.

摘要

2,6-2-{RN=C(H)}C(6)H(4)C(6)H(3)I [R = 苯基 (4)、环己基 (5)、2,6-二甲基苯基 (6)、2,4,6-三甲基苯基 (7)、(S)-α-甲基苄基 (8)] 与 Pd(2)(dba)(3) 反应，通过配体前体的 C-I 键的氧化加成得到 NCN 二亚胺钳形钯配合物 [2,6-2-{RN=C(H)}C(6)H(4)C(6)H(3)PdI] (9 - 13)。配合物 9 - 13 的单晶 X 射线衍射分析揭示了形式上的 C(2) 对称环境。配合物 11 和 12 的变温 NMR 研究表明 N-Ar 键的旋转受阻，并且还表明配合物 9 - 13 的阻转异构体在 NMR 时间尺度上不会相互转化。与该提议一致，有可能分离出 13 的两种可能异构体 (13a 和 13b)，并且已经详细研究了它们的结构和 NMR 性质。