A Selenium-Containing Diarylamido Pincer Ligand: Synthesis and Coordination Chemistry with Group 10 Metals

The
synthesis of new bifunctional organoselenium diarylamine compounds
RN­(4-Me-2-SeMe-C6H3)2 (R = Me: 1; R = tert-butoxycarbonyl (Boc): 2; R = H: 3-H) via aryllithium chemistry is disclosed.
Compound 1 serves as a Se,Se-bidentate neutral ligand toward PdII, forming the coordination
complex {PdCl2[MeN­(4-Me-2-SeMe-C6H3)2-κ2Se)]} (1-Pd) in reaction with [PdCl2(COD)] (COD = 1,5-cyclooctadiene),
while the protio ligand 3-H forms tridentate pincer complexes
[MCl­(N­(4-Me-2-SeMe-C6H3)2)] (M =
Pd: 3-Pd; M = Pt: 3-Pt) with [MCl2(COD)] (M = Pd, Pt) in the presence of triethylamine. Complex 1-Pd does not undergo N–C cleavage at high temperature,
unlike related alkylphosphine-bearing complexes. All compounds have
been characterized by multinuclear (1H, 13C, 77Se) NMR spectroscopy, and crystal structures of 1, 1-Pd, 3-Pd, and 3-Pt are
reported. Additionally, density functional theory calculations have
been performed on the pincer complexes to contrast them with well-known
analogues containing phosphine donor groups.

本研究公开了通过芳基锂化学法合成新型双官能团化有机硒二芳基胺类化合物RN(4-Me-2-SeMe-C6H3)₂（其中R=甲基时记为化合物1；R=叔丁氧羰基(tert-butoxycarbonyl, Boc)时记为化合物2；R=氢时记为3-H）。化合物1可作为Se,Se双齿中性配体与Pd(II)配位，与[PdCl₂(COD)]（COD=1,5-环辛二烯(1,5-cyclooctadiene)）反应生成配位配合物{PdCl₂[MeN(4-Me-2-SeMe-C6H3)₂-κ²Se]}（记为1-Pd）。而质子化配体3-H可在三乙胺存在下，与[MCl₂(COD)]（M=Pd、Pt）反应生成三齿钳形配合物[MCl(N(4-Me-2-SeMe-C6H3)₂)]（其中M=Pd时记为3-Pd；M=Pt时记为3-Pt）。与相关的含烷基膦配体的配合物不同，配合物1-Pd在高温下不会发生N-C键断裂。所有化合物均通过多核（¹H、¹³C、⁷⁷Se）核磁共振（NMR）光谱完成表征，同时报道了化合物1、1-Pd、3-Pd及3-Pt的晶体结构。此外，本研究还对该系列钳形配合物进行了密度泛函理论(density functional theory, DFT)计算，以与已知的含膦供体配体的同类配合物开展对比分析。